Method of modifying polymeric material and use thereof

ABSTRACT

A method of modifying a polymeric material whereby the polymeric material is modified to give a highly durable surface without decreasing its strength. Namely, a polymeric material is modified by the method comprising a combination of an impregnation step, an activation step, a step of grafting a monomer and a step of a treatment with a hydrophilic polymer. Thus, the hydrophilic nature, adhesiveness, and so forth of polymeric materials such as polyolefins can be improved without causing any decrease in the practical strength. The thus obtained polymeric materials are usable in articles with a need for high water absorptivity and high adhesiveness, for example, water-absorbing materials and water-retaining materials for medical, sanitary, cosmetic articles or supplies, agricultural materials, synthetic papers, filters and fiber products for clothes, for improving adhesiveness of composite materials and the like. Among all, these materials are particularly usable in dentition orthodontic appliances, writing implements and battery separators.

TECHNICAL FIELD

The present invention relates to a method of modifing the property of apolymeric material. More particularly, the invention relates to a methodto improve the property of a polymeric material such as a waterabsorption property, an adhesion property, and so forth, withoutdecreasing its strength for a practical use. In addition, the presentinvention relates to the polymeric material obtained by the presentmethod and its use thereof.

BACKGROUND ART

(1) Prior Art for Modification of Surface Property of PolymericMaterials

Polyolefin material, such as polypropylene and polyethylene, isexcellent in lightness, strength, chemical resistance, and so forth, andis widely used for molded goods, such as a film, a non-woven fabric, andautomobile parts, electrical machinery and apparatus parts. However, aspolyolefin materials have a low polarity and a high crystallinity, whichare derived from its chemical structure, they have a small hydrophilicproperty and a difficulty in chemical modification. Therefore, they havea low hydrophilic property and a difficulty in the chemicalmodification. Various surface activation processings such asozonization, plasma treatment, UV irradiation processing, high-pressureelectro-discharge treatment, corona discharge processing, sandblastingprocessing, solvent etching processing, chromium mixed-acid processing,and a flame treatment, and so forth have been tried in order to improvethe hydrophilic property and an adhesive property of the polyolefinmaterial. However, even if any method of the above processes is employedto treat the polyolefin material, we cannot obtain the material whichabsorbs water as much as several times of the original weight of thematerial.

For example, the method of improving plating nature, paint nature, andan adhesive property was examined by performing an ozone oxidationtreatment (JP, 3-103448,A (1991)). However, when only the ozonetreatment is employed to improve the property of the material, verysevere reaction conditions are necessary and they cause the decrease inthe mechanical strength, which makes that the treatment isnon-practical. Furthermore, it is impossible to give a large waterabsorption property to the material only by the ozone treatment. Inorder to modify the materials by the other treatments mentioned above,the following problems are caused; the lowering in mechanical strengthof the material and the high cost for facilities and a waste disposalsystem.

In addition to the direct activation of the surface of polymericmaterials mentioned above, a method to form a layer which consists of acomponent with high reactivity on the surface of polymeric materials wasproposed. For example, it was proposed that vinyl monomers containingester groups were grafted to the nonwoven fabric of polyolefin fiber andthen, the ester groups were hydrolyzed to form acid groups which gave ahydrophilic property and an ion-exchange property (JP, 11-7937,A(1999)). However, a grafting of sufficient amount which gives a highhydrophilic property to polyolefins is not easily attained by the vinylmonomer grafting according to the proposed method. Moreover, the methodrequires the hydrolysis treatment after the grafting, which causes aproblem of taking time and effort.

On the other hand, a method to improve a hydrophilic property ofnonwoven fabrics of polyolefin fiber by the treatment with a hydrophilicresin in the presence of a persulfate was proposed (JP,11-67183,A(1999)). Although this method gave practically a hydrophilic property tothe nonwoven fabrics, the modified hydrophilic property does not give adurability in use. For instance, the hydrophilic property obtained bythis method is lost considerably by washing with a hot detergentsolution. In addition, when the materials such as films and casts otherthan a nonwoven fabric were processed, sufficient hydrophilic propertycould not be given, or the adhesive property by adhesives could not beimproved. A method to modify a hydrophilic property of nonwoven fabricsby coating polyvinyl alcohol (JP,1-248460,A (1989)) was also known.Although the hydrophilic property of the obtained material is high, ithas the problem that the durability of a hydrophilic property is notenough because the process is mere covering.

Previously, the present applicant proposed a method to improve thesurface property or especially the dyeability of polymeric materials,which comprises an activation treatment of the surface of polymericmaterials, a graft polymerization of monomers such as acryl amide, etc.to them or the Hofmann rearrangement of the amide groups which arecontained in grafts (JP,8-109228,A (1997)). Although the polymericmaterials which gave the hydrophilic property on the basis of thismethod can be manufactured by this method, the kind of polymericmaterials which can be applied by the method is limited.

According to these methods, polymeric materials with a high waterabsorption property can be manufactured cheaply and easily. However,when the moldings of the polymeric materials containing additives suchas a stabilizer and an antioxidant are processed to obtain a highdurable hydrophilic property, these additives may reduce the effect ofthe activation process.

The above technical requests are desirable not only for polyolefins butalso the other polymeric materials which have more active surfaceproperty than polyolefins. For example, it is sometimes requested that asurface of a polymeric material is modified to give a desirableproperty.

(2) Prior Art for Dentition Orthodontic Appliances

A dentition orthodontic appliance is used to correct an irregularalignment of teeth by a restitution force which is caused by an elasticsteel wire (so-called arch wire) penetrating through an appliance(so-called bracket) that is bonded to a tooth. In general, a bracket ismade of metal or ceramic. But, brackets made of polymers were producedrecently.

In the brackets made of polymeric materials, a bracket made ofpolycarbonate resin reinforced by glass fiber (a PC bracket) is atypical one, and it was disclosed in a Japanese Patent (JP, No.9-98988,A) and an U.S. Pat. No. 5254992. However, the PC bracket gives alow durability in the adhesive property to teeth and is easily pollutedwhen it is used by fitting to teeth. In addition, it was reported thatthe PC bracket produces bisphenol A which is considered to give anenvironmental pollution. Because of these problems, it is desirable toinvent a bracket made of a polymer resin which is harmless to a livingbody, is not polluted easily, and gives a strong adhesion force toteeth. As the present invention can improve the adhesive property ofpolyolefins which are known to be chemically stable, this techniqueshould be also applied to nylon and polyester, and so forth. Therefore,the present invention can provide the dentition orthodontic applianceswhich are made of ideal polymeric materials. Moreover, the dentitionorthodontic appliances mean not only brackets but also variousappliances which are useful for a dental treatment.

(3) Prior Art for Members in Writing Implements or Painting Tools forStationary or Makeup.

Various members such as ink-collectors (or ink-regulators), ink-tanks,ink-guiding cores, pen cores, center rods for pens, ink-absorbingmaterials made of fibers, ink-retaining sponges, brush heads of brushpens, and so forth are used in writing implements. Almost of thesemembers are generally made of polymeric materials. Because, thepolymeric material gives a high mechanical strength, an easy castingproperty, a chemical resistance, economics, and so forth. Members inwriting imprements which are used to contact to water-soluble inkrequire a wettability to water-soluble ink, an absorptivity of the inkand an ink-retaining property. In order to overcome these requirements,a development in excellent and safety skills to improve the hydrophilicproperty of synthetic polymers has been expected.

One of the typical members of writing implements is an ink collector(which is sometimes called “a collector” in short below). The collectoris explained in detail here. The collector is used in an ink tank of awriting implement where the ink is stored directly and it plays an inkretaining body. When an expansion of the air in an ink tank is caused bya temperature increase or a lowering of the atmosphere pressure, the inkpressured in the ink tank run through several longitudinal channels onthe collector surface and then it is stored in many horizontal channels(which are called as ink-retaining channels) which are perpendicular tothe longitudinal channel. Thus, the outflow of the pressured ink fromair voids and nibs of pens can be avoided. When the temperature or theair pressure are recovered to the original state, it is necessary thatthe ink stored in the ink-retaining channels comes back to the ink tankthrough the longitudinal channels. When a writing implement is used fora long time, a decrease in air pressure in the ink tank is caused by adecrease in the amount of ink. As a result, when the decrease in airpressure is caused to excess, the amount of ink suitable for a goodwriting cannot be drawn from the nib of pens. In order to avoid thisproblem, the pressure in the ink tank must be kept at a given reducedpressure. Therefore, the ink collector has a mechanism that the wastedink is substituted with the corresponding volume of air by thelongitudinal channels in the ink tank. When a writing implement isequipped with an ink tank with an excellent collector whose structure ispreferable for storing ink directly, we can use it with a constantamount of ink from the first writing to the final writing.

In addition, a writing implement with a collector made of syntheticresin has the following advantages. It gives a good consumption of inkas compared with the collector containing an ink absorber made offibers; we can use the ink stored in the collector almost completelywithout leaving it in the ink tank. We can see the amount of ink easilythrough an ink tank which is made of a transparent polymer resin.

Therefore, a collector is an indispensable member for a writingimplement with an ink tank. However, when an ink collector surface hasan insufficient wettability to ink, the ink pressured in the ink tankcannot run smoothly into the ink-retaining channels of the collector andthe retention power of the collector to the ink is too weak to keep theink in the collector, without a capillary attraction. As a result, theink contained in the collector goes out of the ink-retaining channelseasily and the ink outflows from the air voids.

At present, an ABS resin (a three-components copolymer of acrylonitrile,butadiene and styrene) is generally used as a material for thecollector, because of the strength, the casting property, the reasonthat the improvement of the wettability is comparatively easy, and soforth. Collectors cast by the ABS resin are treated by immersing them instrong acids or strong alkalis for several minutes to form hydrophilicgroups on them in order to improve their wettability. For example,chromic mixed acid or sodium hydroxide are used as an acid or an alkali.However, the treatment has the following problems; a dangerous workingand the difficulty in the treatment of waste liquid. In addition, whenthe washing of the collector after the treatment is not carried outcompletely, the following problems are considered to be caused; thewaste liquid of the chemicals in the writing implement changes thequality of ink and causes a definite default in the writing implement.Although the danger in the job is high, the wettability of the inkcollector to ink decreases with the elapse of time and therefore, thetreatment is not satisfied well.

On the other hand, a plasma treatment was carried out to improve thehydrophilic property of ABS resin-made correctors (JP, 05-238186,A(1993)). Furthermore, a method to make a surface treatment with vinylmonomers after the plasma treatment was disclosed (JP, 05-238187,A(1993)). The plasma treatment is suitable for the surface treatment ofmaterials with smooth surface, but it causes a defect in the treatmentof correctors having concavo-convex surface because it cannot give agood result to treat the concave part of correctors.

This problem is similarly seen in the treatment of pen cores made byfiber bundles and porous materials with an ink absorptivity. Namely, itis very difficult to treat the inner part of fiber bundles and porousmaterials by a plasma treatment.

In addition, as the surface treatment of ABS resins is comparativelyeasy, an application of many general methods such as a grafting ofhydrophilic monomers, an ionization radiation, a grafting by UVirradiation, and so forth is possible. However, as each of these methodshas laborious processes and gives some problems in grafting such as asurface irregularity and a difficulty to obtain a controlled amount ofgraft polymers, it's application is not suitable for the treatment ofmaterials such as correctors which need a precise structure.

When collectors and the other members in writing implements are castwith polyolefins such as polyethylene and poplypropylene, it is expectedto give a collector with an excellent chemical resistance, a lightweightand a high-impact property and the other members of writing implement.In addition, the application of these products does not cause theenvironmental pollution and the toxicity of components in combustion gaswhich are problematic in recent years. However, it is very difficult toimprove polyolefin resins by the well-known technique for hydrophilicimprovement so far. Especially, as cast products of polyolefin resinsshould contain many kinds of additives such as stabilizers for polymerresins, chemical destaticizers, and so forth, their treatment to improvethe hydrophilic property is impossible as far as the products are usedas they are. Therefore, there is not an excellent method to give theimprovement expected in the hydrophilic property of collectors and theother members in writing implements as described above. If the techniqueto improve the hydrophilic property of polyolefins including chemicalstabilizers is established, its technique should be applicable for theother materials such as nylon, polyester, wool fiber, cellulose acetate,esters of polyacrylic acids, polyurethane, and so forth because thechemical treatment of these materials are easier than that ofpolyolefins. Therefore, the establishment of the technique for thesurface modification is expected.

(4) Prior Art for Battery Separators:

Battery Separators are used to provide a smooth electromotive reactionin batteries by holding the amount of the electrolytic solution, whileseparating the positive electrode and negative electrode of a chemicalcell and preventing a short circuit from the former. Variousrequirements are dependent on the kind of batteries and a lot ofinventions were carried out.

For example, as the electrolytic solution of an alkaline cell isstrongly alkaline, a battery separator must be an alkali-proof material.A battery separator made of polyamide non-woven fabrics used from thepast has a fault that it elutes nitrogen oxides from the fiber andcontracting the life of a cell by repeat use. Therefore, batteryseparators made of fabrics of polyolefin fibers (a bicomponent fiber isalso included) such as polypropylene and polyethylene which wereexcellent chemical-resistant have been investigated. However, batteryseparators made of polyolefin materials with an excellent durable waterabsorption property are not seen at present.

When polyolefin fabrics with the improved water absorption property areused as battery separators, they are immersed in an aqueous sulfuricacid solution of 40 w/w % concentration in lead storage batteries, or inan aqueous solution of sodium hydroxide of 30 w/w % concentration inalkali batteries. As the charge-discharge process must be repeated inthe batteries for use, the battery separators must give an excellentdurability in the use for a long time as much as possible. For thatpurpose, a development of the method to produce hydrophilic polymericmaterials excellent in chemical resistance, oxidation resistance, and soforth is desired. Further, the method which makes it possible to producethe hydrophilic polymeric material, easily, cheaply and in largequantities is desired in industry.

Although various techniques mentioned in the above “(1) Prior Art forModification of Surface Property of Polymeric Materials” have beenapplied for the modification of materials for battery separators andsome methods have been proposed, the materials satisfying therequirements for battery separators are not obtained.

The present invention intends to overcome the defaults in the previousmethods described above and to provide a method for improving thesurface property of polymeric materials which has an excellentdurability without lowering the practical strength. Furthermore, thepresent invention intends to provide materials with water-absorptionproperty modified for medical, sanitary, or cosmetic supplies such asdisposable diapers, sanitary protection supplies, bandages, gauze,plasters with disinfectants and materials for cleaning and face cleanserpack, and so forth, brackets for dentition orthodontics, water retentionmaterials useful for agriculture or greening in dry districts, materialsfor microorganism culture media, synthetic paper, filter media, medicalimplements (artificial organs, artificial joints, materials molded intubes, strings and plates, and so forth) and polymeric materials withimproved adhesive property and composites containing the said improvedpolymeric materials.

In addition, the aim of the present invention is applicable in commonfor all kinds of synthetic resins, regenerated fibers and naturalfibers. Especially, the present invention gives a useful technique toimprove polyolefins whose chemical modification is known to bedifficult, and provides improved members of writing implements made ofpolyolefins which give the durability in the properties such as awettability to water-soluble ink, an ink-adsorptivity and an ink-holdingproperty.

Furthermore, the present invention intends to provide battery separatorsmade of modified polymeric materials which give an excellent property inkeeping electrolytic solutions in batteries, an alkali-resistance, anacid-resistance, a lightweight and a high mechanical strength, andintends to prepare the battery separator with the following propertiescheaply and easily; that the hydrophilic treatment of the modifiedpolymeric materials is made by real chemical bonds and that theperformance data of the battery are not changed in the use for a longtime, and to prepare the batteries containing these battery separators.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 gives a drawing of a longitudinal section of a writing implementof an example comprising an ink chamber filled with ink and an inkcollector with a comb-teeth shaped section in which a pen core isequipped.

FIG. 2 gives discharge curves of the batteries assembled with variousseparators which were continuously overcharged.

DISCLOSURE OF INVENTION

The present inventor investigated the method for improving the surfaceproperty of polymeric materials wholeheartedly in order to attain theaims described above and discovered that a combination of animpregnation step, an activation step, a step of monomer grafting and astep of treatment with hydrophilic polymers is effective for theimprovement, and completed this invention.

Namely, the present invention relates to the method for modifying thesurface of polymeric materials by the following sequential steps;

-   (1) subjecting the polymeric material to an impregnation step to    contact the polymeric material with a single or mixture of compounds    having an impregnation property to the polymeric material in the    manner so that the content of the impregnated compound in the layer    within the depth of 100 microns from the surface of the polymeric    material is in the range of 0.1% to 40% by weight of the treated    polymeric material without any substantial deformation of the    polymeric material; and-   (2) subjecting the polymeric material produced in said impregnation    step to an activation step to introduce carbonyl groups into the    polymeric material; and-   (3) conducting a step of monomer grafting to the polymeric material    produced in said impregnation step and subsequent said activation    step. This method is called “Modification method 1” below.

Or, the present invention relates to the method for modifying thesurface of polymeric materials by the following sequential steps;

-   (1) subjecting the polymeric material to an impregnation step to    contact the polymeric material with a single or mixture of compounds    having an impregnation property to the polymeric material in the    manner so that the content of the impregnated compound in the layer    within the depth of 100 microns from the surface of the polymeric    material is in the range of 0.1% to 40% by weight of the treated    polymeric material without any substantial deformation of the    polymeric material; and-   (2) subjecting the polymeric material produced in said impregnation    step to an activation step to introduce carbonyl groups into the    polymeric material; and-   (3) subjecting the polymeric material produced in said impregnation    step and subsequent said activation step to a step of treatment with    hydrophilic polymers. This method is called “Modification method 2”    below.

Or, the present invention relates to the method for modifying thesurface of polymeric materials by the following sequential steps;

-   (1) subjecting the polymeric material to an impregnation step to    contact the polymeric material with a single or mixture of compounds    having an impregnation property to the polymeric material in the    manner so that the content of the impregnated compound in the layer    within the depth of 100 microns from the surface of the polymeric    material is in the range of 0.1% to 40% by weight of the treated    polymeric material without any substantial deformation of the    polymeric material; and-   (2) subjecting the polymeric material produced in said impregnation    step to an activation step to introduce carbonyl groups into the    polymeric material; and-   (3) subjecting the polymeric material produced in said impregnation    step and subsequent said activation step to a step of treatment with    hydrophilic polymers; and-   (4) conducting a step of monomer grafting to the polymeric material    produced in said impregnation step and subsequent said activation    step. This method is called “Modification method 3” below.

The present invention is explained in detail below.

(Polymeric Materials)

Polymeric materials used in the present invention include the polymermaterial contained in each of a single polymer or a mixture of polymers,a modified single polymer or polymer mixture, a material prepared bymixing or conjugating the polymers with glass, metal and carbon fiber,and so forth. Both thermoplastic polymers and thermosetting polymers areused as synthetic polymers. Various methods are exemplified for thepreparation of these polymers, and all polymers prepared by thesemethods can be used in the present invention. For example, the followingpolymers are available; (1) homopolymers or copolymers prepared by theaddition polymerization of monomers selected from olefins, vinylcompounds except olefins, vinylidene compounds and the other compoundswith carbon-carbon double bonds, (2) polymers prepared by thepolycondensation such as polyesters and polyamides, and so forth or themixture of these polymers or the modified polymers, (3) polymersprepared by the addition polycondensation such as phenol resin(containing Kynol (a commercial name of Japan Kynol Co., Ltd.), urearesin, melamine resin, xylene resin,and so forth or the mixture of thesepolymers or the modified polymers, (4) polymers prepared by thepolyaddition such as polyurethane, polyurea, and so forth or the mixtureof polymers or the modified polymers, (5) homopolymers or copolymersprepared by the ring-opening polymerization of cyclopropane, ethyleneoxide, propylene oxide, lactone and lactam, or the mixture ofhomopolymers or copolymers or the modified polymers, (6) cyclic polymersprepared by the polymerization of divinyl compounds (e.g.,1,4-pentadiene) or the mixture of homopolymers or copolymers or themodified polymers, (7) polymers prepared by the isomeric polymerization;e.g., alternative copolymer of ethylene and isobutene, and so forth, (8)homopolymers or copolymers prepared by the electrolytic polymerizationof pyrrole, aniline and acetylene, and so forth, or the mixture of thesehomopolymers or copolymers or the modified polymers, (9) polymersprepared by the polymerization of aldehydes and ketones,and so forth,(10) poly(ethersulfone), (11) polypeptides, and so forth. As naturalpolymers, a single material or a mixture of cellulose, proteins andpolysaccharides or these derivatives, and so forth are given. In thepresent invention, the polymers made by the addition polymerizationdescribed above are preferably used. Monomers used in the additionpolymerization are not specially limited. Homopoymers or copolymers ofalpha-olefins such as ethylene, propylene, butene-1, hexene-1,4-methylpentene-1 and octene-1, and so forth and the mixture ofhomopolymers and/or copolymers are expedientially used.

In the present invention, “vinyl compounds except olefins” mean thecompounds containing vinyl groups. For example, the following compoundsare given; vinyl chloride, styrene, acrylic acid, methacrylic acid,esters of acrylic or methacrylic acids, vinyl acetate, vinyl ethers,vinyl carbazole, acrylonitrile, and so forth. “Vinylidene compoundsexcept olefins” mean the compounds containing vinylidene groups;vinylidene chloride, vinylidene fluoride, isobutylene, and so forth areexemplified. “Compounds containing carbon-carbon double bonds exceptolefins, vinyl compounds and vinylidene compounds give the followingcompounds; maleic anhydride, pyromellitic dianhydride, 2-butene acid,tetrafluoroethylene and chlorotrifuluoroethylene, and so forth andcompounds containing two or more vinyl groups; butadiene, isoprene andchloroprene, and so forth are exemplified.

As preferable polymers prepared by the addition polymerization,homopolymers or copolymers prepared by the polymerization of two or moremonomers selected from these monomers and mixtures of these polymers canbe expedientially used. Especially, polyethylene, a copolymer ofethylene and the other alpha-olefins, polypropylene and a copolymer ofpropylene and the other alpha-olefins are preferably used. Thesecopolymers contain both of random copolymers and block copolymers.

As this invention is effective for improving a hydrophilic property ofpolyolefins whose chemical modification or treatment is considered to beextremely difficult, polyolefins are preferably used.

In addition to polyolefins, polymeric materials such as homopolymers orcopolymers obtained by the polymerization of one or more monomers whichare selected from the group comprising vinyl compounds, vinylidenecompounds or compounds containing carbon-carbon double bonds; forexample, poly(methacrylic acid ester)s resin, poly(acrylic acid ester)sresin, polystyrene, polytetrafluoroethylene, copolymers of acrylonitrile(acrylic fibers and their cast materials, ABS resin, and so forth),copolymers containing butadiene (synthetic rubbers), and so forth,polyamides (containing nylon and aliphatic or aromatic polyamides),polyesters (containing polyethylene terephthalate and aliphatic orall-aromatic polyesters), polycarbonate, polyurethane, polybenzoate,polyethersulfone, polyacetal and various kinds of synthetic rubbers, andso forth are preferably used.

In addition to polymers described above, the following polymers areexamplified; polyacetals, polyphenols, poly(phenylene ether)s,poly(alkyl-p-hydroxybenzoate), polyimides, poly(benzimidazole),poly-(p-phenylene benzbisthiazole), poly-(p-phenylene benzbisoxazole),poly(benzthiazole) and poly(benzoxazole), and the fibers of thefollowing materials are preferably used; cellulose acetate, regeneratedcellulose (viscose rayon, cuprammonium rayon, polynosic, and so forth),vinylon and a copolymer of vinylalcohol and vinylchloride (polychlal; acommercial name, Cordera), and so on. In addition, carbon fibers andnatural fibers; vegetable fibers such as cotton, hemp, flax, ramie andjute, and so on, and animal fibers such silk and wool, and so on arealso used. Moreover, the mixture or the conjugate materials containingthese polymers are preferably used.

The present invention is applicable for not only the polymeric materialsdescribed above but also all kinds of polymers.

Even if the polymeric materials contain antioxidants, stabilizers,nucleation agents, flame retardants, fillers or bulking agents, foamingagents, antistatic additives, and various additives which are usuallyadded in polymeric materials, they can be improved by the presentinvention. In general, the modification of polymeric materialscontaining the additives such as antioxidants and so on is known to bevery difficult because these additives prevent the activation of thesurface of the polymeric materials. In general, the existence ofadditives such as antioxidants and so forth in polymeric materials areconsidered to be not preferable for their modification, because theseadditives prevent the activation of the surface of the polymericmaterials. Therefore, it is considered to be preferable to prepare thepolymeric materials with no additives or to remove additives from thepolymeric materials containing them. Contrary to this aspect, thetechnique in the present invention attains an effective surfacemodification for the polymeric materials containing additives such asstabilizers, and so forth. Therefore, this invention can be applicablefor a cast polymeric material itself which is prepared by a usualmethod.

(Form of Polymeric Materials)

In the present invention, the form of the moldings of the polymericmaterials to be improved is not especially limited. For example, fibers,woven fabrics, non-woven fabrics, cloth, a board, a film, a sheet, apipe, a rod, a hollow container, a box, a foam and a layered product,and so forth are available. From a viewpoint of the improvement of thewater absorptivity, especially moldings, such as fiber, textiles, anon-woven fabric, cloth, a film, and a sheet can be processed easily.Porous films and sheets prepared for filtration mediums or syntheticpapers are easily modified to give a durable water absorption property.In addition, when the present invention is applied to the modificationof the members or parts of products molded in a predetermined from, thepolymeric materials which have not been used conventionally were madeusable. When the other various plastic materials (volts, nuts, chains,parts of electronics, caps, covers, and so forth) are treated by thepresent method, their wettability and adhesion property are improved andthe electrification is decreased.

As fiber or textiles, various fibers, textiles and non-woven fabrics ofthese fibers are preferably used. Each form of fibers is available; afiber made of a single component, a mixture of two or more sorts offibers, mixed fibers and a conjugate fiber (a sheath-core type, aside-by-side aligned type, a multicore type, a multi-island-in-the-seatype, a hollow-segment-pie type, and so forth).

(Members of Writing Implements)

Members of writing implements are composed of polymeric materials andtheir forms are given as follows; an ink corrector, an ink tank, anink-guiding core, a pen core, a center rod in a pen, an ink-absorbingmaterials made of fibers, an ink-retaining sponge, a brush head of abrush pen, and a brush pen for painting colors, a brush pen for makeup,and so forth. Furthermore, a cap, an inner-cap and a plastic-mademouthpiece, and so forth are given. In addition, plastic members forsealing or fitting are given. Considering the structure of members, pencores, ink-introducing cores, ink-retaining members andtemporary-ink-retaining bodies which are made of porous materialsprepared by the fusion bonding or adhesive bonding with resin particles,or pen cores, ink-guiding cores, ink-retaining members andtemporary-ink-retaining bodies which are made by fusion bonding oradhesive bonding of polymer short fibers, polymer long fibers or amixture of short or long fibers of polymers.

(Battery Separators)

Preferable forms of polymeric materials for preparing battery separatorsare given as follows; non-woven fabrics, porous sheets, porous films,non-woven fabrics, board-like composites containing fibers, cloths, andso forth. In order to prepare separators for alkali batteries, non-wovenfabrics having a pore size of 1 to 200 microns, a vacancy of 30 volume %to 80 volume %, a thickness of 20-500 microns, a fiber diameter of0.1-100 microns and a density of 5 g/m² to 100 g/m² are preferably used.Using these materials, battery separators which give a high wettabilityto electrolytic solutions, a high retaining property of electrolyticsolutions, a good permeability for oxygen generated from the positiveelectrode in the course of an electric charge and an excellent strengthcan be produced. In addition, as separators for lead-storage batteries,a composite which is prepared by bonding a coarse glass-fiber sheet withpolyolefin fibers by the thermal fusion bonding or adhesive resins ispreferably used. Battery separators for the lead-storage battery as acidbatteries require an appropriate thickness, a high strength and a highretaining property of electrolytic solutions. Considering theseconditions, non-woven fabrics having a pore size of 1 to 200 microns, avacancy of 30 volume % to 80 volume %, a thickness of 500 microns to1200 microns, a fiber diameter of 0.1-100 microns and a density of 100g/m² to 300 g/m² are preferably used.

Each of modification method relating to the present invention is givenbelow.

(Washing)

It is preferable to wash the surface of polymeric materials to removesome impurities with an appropriate liquid before the processing. Forexample, polyolefins, polyvinylchloride, polyvinylidene chloride, and soforth are washed preferably with toluene. Cellulose acetate, nylons,polyesters, polystyrene, acrylic resins, polyvinyl acetate,polycarbonate and polyurethane, and so forth are washed preferably withalcohols. Cellulose derivatives such as viscose rayon and cuprammoniumrayon, and so forth are washed preferably with an aqueous soap solutionfirst and with alcohols later.

(Impregnation Step)

The impregnation step is carried out by touching the polymeric materialsto the compounds which are impregnated in them at a temperature underthe softening point of the polymeric materials; the said compoundshaving affinity to polymeric materials are used as they are or assolutions or dispersants. In this step, polymeric materials give noessential deformations. The compounds used for this aim are called as“impregnants”. This impregnation step is explained as follows; theimpregnants permeate in the crystal region of the polymeric materialsand make very small interstices in the materials. This step has a roleto proceed the subsequent activation step and grafting step. Theimpregnants contained in the polymeric materials can be removed bywashing after the subsequent steps.

The preferable range of the amount of impregnants in the polymericmaterials are given as follow; 0.1-40 weight % for the polymericmaterials whose thickness is below 1000 micron and the content in theregion of the materials within 1000 micron depth from the surface is0.1-40 weight % for the polymeric materials with a thickness of over1000 micron. In the case of the polymeric materials with a thickness ofboards or a diameter of rods are below 20 mm, the impregnating contentis preferably 0.1-10 weight %.

(Impregnants)

As impregnants, each of compounds with an affinity to the polymericmaterials are used; inorganic or organic compounds and gaseous, liquidor solid compounds are similarly useful. Liquid impregnants can be usedas they are or their mixtures are used as solutions or dispersionsprepared by mixing with the other liquids. When the impregnants aresolid, they are used as solutions, dispersions or emulsions by mixingwith the other liquids. When the impregnants are gaseous, they are usedas they are. The impregnants in the present invention contain aso-called solvent. However, the kind of impregnants is not limited tothis.

Impregnants are usually selected by considering the kind of polymericmaterials which are processed. Compounds used in the carrier dyeing ofsynthetic fibers, especially polyesters or commercial carriers arepreferably used. In addition, a lot of compounds corresponding to thecarriers can be used. These compounds can be widely useful for not onlypolyesters but also polyolefins, polystyrene, polyacrylate resins,polyurethane, and so forth. Diphenyl, ortho- or para-hydroxybiphenyls,the other derivatives of diphenyl, sodium salicylate or its derivatives,halogenated aromatic compounds (for example, mono-, di- ortrichlorobenzene), and so forth are exemplified. These compounds can beused as solutions in organic solvents such as hexane, methanol, and soforth, dispersions in water or emulsions containing surfactants.

Moreover, liquids of organic compounds which have the compatibility tothe polymeric materials can be also used as impregnants. As a matter ofconvenience, the following requirement is useful to decide an impregnantfor a polymeric material; a single compound or a mixture of pluralcompounds selected from the liquids of organic compounds whosesolubility parameters (SP) are close to those of the polymeric materialswhich are treated. It is preferable that a polymeric material is treatedwith a solvent whose difference of the solubility parameter from that ofthe polymeric material is in the range of −2 to +2. When the differenceof SP between a solvent and a polymeric material is smaller than thisrange, the polymeric material must be treated very quickly with thesolvent at temperature much lower than usual room temperature. Thesolvent does not dissolve the polymeric material but it should be onlyimpregnated into the surface of it. When an organic solvent dissolves apolymeric material at high temperature, it can be used for a short timeat low temperature where the polymer is not dissolved by the solvent. Asexamples of liquid impregnants, toluene, xylene, decalin, tetralin,cyclohexane and a mixture of dichloroethane and ethanol (1:2, volumeratio),and so forth are useful for polypropylene, a mixture of tolueneand methanol (1:10, volume ratio), and so forth are useful forpolystyrene and a mixture of phenol and hexane (1:10, volume ratio), andso forth are useful for polyethylene terephthalate.

Conditions for the impregnation step such as temperatures, times, and soforth are selected preferably by considering the form or shape of thepolymeric materials to be treated. We can select the appropriateconditions for the aim of the treatment. For example, when a non-wovenfabric composed of polyolefin fibers with a diameter of 5-19 micron istreated, it is immersed in an impregnant (for example, toluene) for twominutes at room temperature and the impregnant in the fabric is removedby a centrifugal separator (a rotation rate: 500-2000 rpm). When thesurface of the polymeric material seems dry, the impregnation process isfinished. In the treatment of films, boards and cast materials (athickness about 2-5 mm) made of polyolefins, the material is immersed inan impregnant for 5-30 minutes at from room temperature to 70° C. andthe impregnant is removed similarly to the manner mentioned above. Theweight increase in the polymeric material through the impregnation stepis about 1-10 weight %.

In the impregnation step of wool fiber, it is immersed in a mixture ofan aqueous solution of sodium carbonate and methanol for 1-10 minutes atroom temperature, and the material is rinsed with methanol and theimpregnant is removed by a centrifugal separator.

The present impregnation step is useful for the treatment of moldedmaterials with a small surface area such as films and boards ormaterials which contain a lot of antioxidants and the other additives.

(Activation Treatment Step)

In the present invention, the activation treatment step means thetreatment to introduce carbonyl groups into the surface of materials. Inaddition to carbonyl groups, the activation treatment process gives theintroduction of functional groups or unsaturated bonds containing oxygenor nitrogen, and so forth to the materials. A preferable activationtreatment process is each of treatments such as a plasma treatment, anozone treatment, an ultraviolet light irradiation, a corona discharge, ahigh-voltage electric discharge, and so forth. Well-known facilities areavailable for the aim of the present invention. The extent of theactivation treatment is appropriately controlled by considering the aimof the treatment. An introduction of a trace amount of carbonyl groupsin polymeric materials is a preferable activation treatment for thepresent invention. Generally, activation treatments which were proposedso far are too hard to attain the aim of the present invention. As anindication of the activation treatment, an infrared spectroscopy (IR) oftreated polymeric materials is effective to observe the extent of theactivation treatment. For example, a ratio of the absorbance due tocarbonyl groups introduced in materials to that due to the crystallineregion which is not changed by the treatment is estimated by the baseline method and the result is used to see the extent of the oxidation bythe activation treatment.

For example, in the case of polypropylene, it is preferable that theratio of the absorbance at around 1710 cm⁻¹ due to the carbonyl groupsintroduced in the polymer to the absorbance at around 973 cm⁻¹ due tothe methyl groups unchanged in the crystalline region is about 0.2 orless.

A preferable method to determine the conditions of the activationtreatment is as follows: the relationship between a treatment time andan absorption due to introduced carbonyl groups in the activation ofobjective materials is previously observed and their relationalexpression is estimated. The condition of the activation treatment whichdoes not give a decrease in strength of the treated material isdetermined from the relational expression. When a decrease in thestrength is observed for the treated material even if the infraredspectroscopy indicates only the existence of a trace amount of carbonylgroups which is in a limit of the IR measurement, the appropriatetreatment time can be estimated by the extrapolation from the relationalexpression in the region which cannot be observed by IR. In this way, aneffective activation treatment for materials which gives no decrease inthe strength can be attained.

(Ozone Treatment)

The ozone treatment is carried out in order to cause a chemicalreaction, mainly oxidation of the surface of polymeric materials bycontacting ozone molecules to the polymeric materials. The ozonetreatment is performed by exposing polymeric materials to ozone. Anymethods of the exposing procedures can be available; for instance, toput a polymeric material under an ozone atmosphere for a given time, toexpose a polymeric material in a stream of ozone, and so forth. Ozonecan be generated by supplying air, oxygen, or gas containing oxygen suchas oxygen-added air, and so forth to an ozone generator. The ozonetreatment is carried out by introducing the obtained gas containingozone into a reaction vessel or a container in which polymeric materialsare involved. The conditions of ozone treatment such as a concentrationof ozone in a gas containing ozone, an exposure time, temperature, andso forth are appropriately determined by considering a kind and a formof a polymeric material and the aim of the surface modification.

Generally, a stream of oxygen or air with a flow rate of 20 ml/min.−10L/min. is used to generate ozone with a concentration from 10 g/m³. to200 g/m³., and polymeric materials are treated in it at temperature from10° C. to 80° C. and a reaction time from 1 minute to 10 hours.

For example, the treatment with an ozone concentration from 10 to 40g/m³ and a time from about 10 to 30 minutes at room temperature isavailable for the treatment of polypropylene fibers or polyvinylchloride fibers. When the specimen is a film, an appropriate ozonetreatment is carried out with an ozone concentration from 10 to 80 g/m³for the time from about 20 minutes to 3 hours at room temperature. Whenair is used instead of oxygen, the ozone concentration becomes about ahalf of that with oxygen.

It is considered that hydroperoxide groups (—O—OH), and so forth areintroduced to the surface of polymeric materials by the reaction, mainlyoxidation, using the ozone treatment and some of them are considered tobe changed to hydroxide groups or carbonyl groups.

(Plasma Treatment)

A plasma treatment is carried out to introduce functional groupscontaining oxygen, nitrogen, and so forth to the surface of materials; apolymeric material is put in a vessel containing a gas such as argon,neon, helium, nitrogen, carbon dioxide, oxygen and air, and so forth andthe material is exposed to the plasma generated by a glow discharge. Itis considered that radicals are generated on the surface of thepolymeric material by the attack of the plasma. Subsequently, theradicals are exposed to air and reacted with oxygen to form carboxylicgroups, carbonyl groups, amino groups, and so forth are considered to beproduced on the surface of the polymeric material. Furthermore, theplasma treatment under a low pressure of nitrogen, oxygen or air canproduce functional groups directly on the polymeric material. Methods ofthe electric discharge for the generation of plasma are classified in(1) a direct current discharge, (2) a radio-wave discharge, (3) amicrowave discharge, and so forth.

(Ultraviolet Light Radiation Treatment)

An ultraviolet light radiation treatment is a method to irradiate anultraviolet light (generally expressed by UV, or UV light in short) tothe surface of polymeric materials. Low-pressure mercury lamps,high-pressure mercury lamps, super high-pressure mercury lamps, xenonlamps, metal halide lamps, and so forth are employed as a UV lightsource. It is effective that a polymeric material is treated with asolvent which can absorb UV light before the UV irradiation. Althoughany wave length of UV light is available, that of around 360 nm or alittle less is preferable to avoid the degradation of the material. Whena UV light is irradiated to a polymeric material, a part of the light isabsorbed by several chemical structures such as double bonds, and soforth in the surface region of the polymeric material and the absorbedenergy should break some chemical bonds to form radicals. The resultingradicals are considered to form carboxylic groups or carbonyl groups viaperoxides by the reaction with oxygen in air.

(High Electric Voltage Treatment)

A high electric voltage treatment is as follows. A polymeric material isput on a belt conveyor roller equipped in a tunnel-shaped implement andthe material is put on the belt. A high voltage such as several hundredthousands volts is charged between many electrodes equipped in the innerwall of the implement and the electric discharge was made in air. It isconsidered that the electric discharge activates oxygen in air and thesurface of the material and that the oxygen included in the materialsurface forms polar groups in it.

(Corona Discharge Treatment)

A corona discharge treatment is as follows. A polymeric materials islaid on a metal roller which is grounded, and a high voltage such asseveral thousands volts is added between the metal roller and theknife-shaped electrodes which are aligned with intervals of several mmdistance against the metal roller. A corona discharge is generatedbetween the metal roller and the electrodes in air and a polymericmaterial is passed through the space between the metal roller and theelectrodes. This method is suitable for films or thin materials.

The methods except the ozone treatment are based on an energyirradiation. When a polymeric material has a part which makes a shadowfor the irradiation, a technique is necessary to treat the shadow partby the irradiation. Therefore, the ozone treatment is preferable for thetreatment of materials such as a non-woven fabric and a fiber-assembledmaterial which give shadow parts derived from the material's structure.Besides, the ozone treatment is economical and preferable because of theeconomical equipment.

(Monomer Grafting Treatment)

In the present invention, monomers used for grafting are not limited asfar as they are graft polymerizable compounds; compounds with at leastone carbon-carbon double bond, for instance, vinyl compounds or similarcompounds to them are preferable. Hydrophilic monomers are morepreferable among monomers. As hydrophilic monomers, at least a singlemonomer or a mixture of monomers selected from the following group arepreferably used; acrylic, acid, methacrylic acid, vinyl acetate,2-butene acid, ethylene sulfonic acid, hydroxyalkyl acrylate,hydroxyalkyl methacrylate, acryl amide, vinyl pyridine, vinylpyrrolidone, vinyl carbazole, maleic anhydride and pyromelliticdianhydride. In the present invention, the use of acrylic acid ormethacrylic acid is especially preferable because their polymer give ahigh chemical resistance and a high water absorption property.

In addition, as vinyl monomers whose hydrophilic properties are lessthan hydrophilic monomers, the following monomers are also available;esters of acrylic acid, esters of methacrylic acid, vinyl acetate,styrene, and so forth. A use of only hydrophilic monomers is preferable,but, sometimes, a use of a mixture of hydrophilic monomers with lowhydrophilic monomers is effective for increasing the amount of grafting,as a result, the hydrophilic monomer residues contained in the grafts onthe polymeric materials can indicate a hydrophilic property.

As the methods of monomer grafting, each of the following methods isavailable; (1) a method to carry out the monomer grafting in thepresence of catalysts or initiators (the general term is given as“initiators” below), (2) a method to carry out the monomer grafting byheating in the presence or absence of catalysts or initiators, and (3) amethod to carry out the monomer grafting by UV irradiation in thepresence or absence of catalysts or initiators.

The following initiators are exemplified; the combination of peroxides(benzoyl peroxide, t-butylhydroxy peroxide, di-t-butylhydroxy peroxide,and so forth.), cerium ammonium nitrate (IV), persulfates (potassiumpersulfate, ammonium persulfate, and so forth.), oxidation-reductioninitiators (oxidants: persulfates, hydrogen peroxide, hydroperoxide, andso forth., and inorganic reductants: copper salts, iron salts, sodiumhydrogen sulfite, sodium thiosulfate, and so forth, and organicreductants: alcohols, amines, oxalic acid, and so forth., and then thecombination of the oxidants: hydrogen peroxide and so forth, andinorganic reductunts: copper salts, iron falts, sodium hydrogensulfite,sodium thiosulfite, and so forth, or organic reductants: dialkylperoxides, diacyl perozides, and so forth, and reductants: tertiaryamines, naphthenates, mercaptans, organometallic compounds (triethylaluminium, triethyl boron, and so forth), the other usual well-knowninitiators for radical polymerization, and so forth.

When acrylic acid is used as a monomer, a water-soluble initiator suchas cerium ammonium nitrate (IV) or potassium persulfate, and so forth.are preferably used. A water-insoluble initiator such as benzoylperoxide or N, N′-azobisisobutylonitrile (AIBN) is dissolved in methanolor acetone and the obtained solution is used after being mixed withwater. In the grafting by a UV irradiation, a photo-sensitizer such asbenzophenone , hydrogen peroxide, and so forth can be used, in additionto the initiators mentioned above.

A monomer grafting is carried out by general grafting methods. Namely,the monomer grafting can be attained by the reaction in each of liquidphase, gaseous phase and solid phase.

When a water-soluble initiator is used, an appropriate amount of themonomer necessary for the treatment is dissolved in water. If awater-insoluble initiator is used, it is dissolved in an organic solventsuch as alcohols, acetone, and so forth which are miscible in water, andthe solution of the initiator is mixed with an appropriate amount ofwater, taking care not to precipitate. A polymeric material treated byan activation step or a step with a hydrophilic polymer explained belowis put in a solution of an initiator, and its monomer grafting iscarried out by adding a monomer in the mixture. The atmosphere in thereaction vessel is substituted by nitrogen if necessary. When a thermalgrafting is carried out, the reaction mixture is heated for a given timeat a given temperature. Furthermore, when a monomer grafting is carriedout by a UV irradiation, a UV irradiation is made to the reactionmixture for a given time at a given temperature. UV lamps are notlimited by special ones. A high pressure mercury lamp (for example, alamp, H400P produced by Toshiba Co., Ltd.) can be used. UV light withwavelength of about 360 nm monochromated by a filter is applicable, butUV light with a whole wavelength range generated by a UV lamp can bealso used.

When a monomer for grafting is a volatile compound, the vaporizedmonomer can be used for the grafting. Namely, a polymeric material whichwas pretreated is put in a sealed reaction vessel and a volatile monomer(for example, methyl methacrylate, styrene, and so forth.) is injectedinto the vessel. The reaction vessel containing the reaction mixture isevacuated to a given reduced pressure and the monomer is gasified in it.The reaction vessel is then made by a UV irradiation and the monomergrafting is attained.

When a vinyl monomer containing amide groups is used as a monomer forthe grafting, the Hoffman rearrangement to the graft polymer obtained inthe polymeric material is preferably used according to the method asdescribed in JP,H8-109228, A(2006) by the present applicant.

(Hydrophilic Polymer)

The polymeric materials modified by the method of the present inventionare improved in the following properties; by the method of the opreInthe present invention, “hydrophilic polymers” represents water-solublepolymers or polymers which do not dissolve easily in water but have ahydrophilic property. Specific examples of polymers are as follows;poly(vinyl alcohol), sodium carboxymethyl cellulose, ethylene-vinylalcohol copolymer, poly(hydroxyethyl methacrylate), poly(alpha-hydroxyvinyl alcohol), poly(acrylic acid), poly(alpha-hydroxy acrylic acid),poly(vinyl pyrrolidone) and poly(alkylene glycol)s such as poly(ethyleneglycol) and poly(propylene glycol), and so forth. In addition, thesesulfonates can also be available. In addition, sodium arginate, starch,silk fibroin, silk sericin, gelatin, various kinds of proteins,polysaccharides, and so forth are exemplified.

(Step of Hydrophilic Polymer Treatment)

When a step of hydrophilic polymer treatment is carried out to apolymeric material which have been treated by an activation step, it ispreferable to attain the step in the presence of catalysts orinitiators. The catalysts or initiators used in “the monomer grafting”described above are similarly used in the step of hydrophilic polymertreatment.

In the step of hydrophilic polymer treatment, it is preferable to use anaqueous solution of a hydrophilic polymer. A water-soluble polymer isused as an aqueous solution. If a hydrophilic polymer is not solubleeasily in water, it can be used as a solution in an appropriate solvent.The use of water-soluble polymers is explained below.

When a treatment with a water-soluble polymer is carried out in theabsence of an initiator, a polymeric material treated by the activationstep is put in an aqueous solution of the water-soluble polymer.

When a treatment with a water-soluble polymer is carried out in thepresence of an initiator, at first, an aqueous solution of thewater-soluble polymer is prepared. Then, if the initiator iswater-soluble, a given amount of it is dissolved in the aqueous solutionof the water-soluble polymer. If the initiator is not dissolved inwater, it is dissolved in an organic solvent such as alcohols, acetone,and so forth which are miscible with water, and then, the solution isadded in the aqueous solution of the water-soluble polymer. Then, apolymeric material obtained by the activation treatment is put in thesolution of the water-soluble polymer and the initiator. The inneratmosphere of the reaction vessel is desirable to be substituted withnitrogen gas, but the nitrogen atmosphere is not always necessary forattaining the process simply.

The temperature is not limited for the treatment with a water-solublepolymer and an initiator; usually, the temperature from 10° C. to 80° C.is available, but that from 60° C. to 90° C. is preferable. Thetreatment for a long time (for example, about 12 hours) at a hightemperature is also carried out in order to obtain a durable hydrophilicproperty to a polymeric material.

(Uses)

Polymeric materials modified by the method of the present invention givethe extremely improvement in the properties as follows; water absorptionproperty, water retention property, adhesion property, chemicalresistance, and so forth. These results can be available for manyapplications. As an adhesion property of a polymeric material isimproved, for example, it can be bonded to paper, wood, metal, and soforth, using general adhesives such as starch, poly(vinyl acetate),epoxy resin, poly(cyanoacrylate), and so forth. The present invention isapplicable for various materials which need an adhesion property.Furthermore, As the present invention is used for the improvement ofpolyolefins such as polypropylene and polyethylene whose improvement isknown to be difficult, it can be applied to modify the other many kindsof polymeric materials. To non-woven fabrics of polyolefin or that of amixture of polyolefin and another polymer, a water absorption of 7 to 10times as much as the original weight is given by this method. Inaddition, the improved materials give a good adhesion property andresistances to alkalis, acids and oxidants. Each of typical applicationsis described below, but the use of the present invention is not limitedto these applications.

(1) Tools or Materials for Wiping or Cleaning: at present, as adisposable wiping or cleaning material for a family use is made by thefollowing procedure and is marketed; as a main basic material, a mixtureof polyester fiber, polyolefin fiber, and the other synthetic fiber isprepared, and further, a rayon fiber is mixed with them to give ahydrophilic property and then, a surfactant is impregnated to the mixedfibers. If this disposable cleaning material is produced using thematerials prepared by the method of the present invention, the productgives a lightweight, a high strength, a high absorption property ofwater or an aqueous surfactant solution, and a high durability for use.It can be used repeatedly several times by rinsing with water.

(2) Water Absorptive Materials: materials with a water absorptionproperty prepared by the present invention are represented.

(3) Water Retention Materials: a hydrophilic polyolefin non-woven fabricprepared by the present invention is useful for a water retentionmaterial which is available for supplying water to plants. To prepare awater retention material, the material of clothes, non-woven fabrics,fibers, and short-cut fibrous waste products are available. Fibers witha diameter of from 10 microns to 500 microns are preferably available.

(4) Medical, Sanitary or Cosmetic Supplies: disposable materials usefulfor medical, sanitary, or cosmetic articles are represented. Diapers,sanitary protections, bandages, gauze, sanitary napkins, disinfectingpatches or tapes, the other medical implements, cosmetic supplies ormaterials for cleaning, cleansing, face packing, makeup, padding, and soforth are exemplified.

The inner part of disposable diapers or sanitary protections containsmaterials having a water retention property which are made of pulp,starch, polyacrylic acid, and so forth and the outside part of them iscovered with a material having a water repellency which prevents thepassing of urine, water, blood, and so forth.

Water which is generated from a body is passed through the innerhydrophilic non-woven fabric and the water is absorbed in the materialswith a water retention property. A hydrophillc polypropylene is the mostpreferable material, because it is strong to water and not brokeneasily. However, the hydrophilic non-woven fabric used in an innermaterial is prepared only by dipping a non-woven fabric in an aqueoussolution of a surfactant or a water-soluble reagent. The productprepared in this way should have no durability to washing; the additiveis easily removed by rinsing with water. In addition, the effect of asurfactant to skins may be a problem to be worried. Thus, a developmentto prepare a polymeric material with a hydrophilic property, cheaply andeasily is desired. Polyolefin materials improved in a water absorptionor retention property which are prepared by the present invention arethe most favorable materials for the inner sewing cloth of thedisposable diapers and sanitary protections. In addition, polymermaterials with a high water absorption property which are prepared bythe present invention are also available for the water absorptionmaterial used in an inner pad of disposable diapers or sanitaryprotections. The hydrophilic material obtained by the present inventiongives a lightweight, a mechanical strength, a safety, and a durabilityfor repeating uses. In addition, as the polymeric material having ahydrophilic property or a water absorption property which is obtained bythe present invention is lightweight and strong, and it can beimpregnated with detergents, chemicals, adhesives and so forth, it isavailable for gauze, a fiber product for wiping, disinfecting clothpatches or tapes, and the other cosmetic articles or supplies. When theyare used for disposable medical, sanitary, or cosmetic articles orsupplies, a preferable material form is a cloth or a non-woven fabric,and its unit weight and thickness of the material are appropriatelyselected. However, a fiber in cloth or a non-woven fabric with adiameter of a range of 1 micron to 500 microns are used easily.

(5) Internal Materials for Clothes, Beds, and Bedclothes: the polymermaterials having a hydrophilic property or a water absorption propertyobtained by the present invention are lightweight and mechanicallystrong. When their water absorption ability is controlled in apreferable extent, they are suitable for fiber products of clothes andan inner material for beds and bedclothes.

(6) Filter Mediums: filters of porous films made of hydrophobicmaterials such as polyolefins, polysulfone, a polyester, and so forth,have a mechanical strength and a low hydrophobic property as comparedwith paper filters. They are not available for the filtration of aqueoussolutions because of the low hydrophilicity. At present, they are coatedwith surfactants or water-soluble polymers in order to improve thehydrophilicity. However, the hydrophilic portions of these filters isnon-durable and is easily dissolved in water in the course of thefiltration. When the hydrophilic treatment of the present invention isapplied for the filter mediums, the filter mediums with a durable waterabsorption property can be obtained.

(7) Materials for Microbial Culture Mediums: as water retentionmaterials obtained by the present invention give a high water absorptionproperty, a high mechanical strength and a high microbial fertility,they are suitable for the materials for a microbial culture medium.Various forms of materials such as clothes, non-woven fabrics, fibersand cut disposable fibers are available. A diameter of component fibersin these materials is preferably from 10 microns to 500 microns.

(8) Dental Treatment Appliance: the treatment method of the presentinvention can modify the adhesion property of polymer materials whichconstitute materials for dental treatment. As the present treatmentmethod can be available for various materials which need a good adhesionproperty, composite materials and fibers used in fiber-reinforcedplastics, it is also useful for the improvement of the adhesion propertyof a plastic appliance for dentition orthodontics (for example,brackets) and the other appliances for dentition orthodontics.

(9) Members of Writing Implements: as the treatment method of thepresent invention can be applicable for usual resins such as polyolefinresins, nylon, polyester, polyurethane, and so forth, it is applied toimprove the property of members in writing implements for stationeryproducts, cosmetic implements, tools, and so forth. The followingwriting implements which need a wettability to ink, an ink-absorbingproperty and an ink-retaining property are exemplified; an inkcollector, an ink tank, an ink-guiding core, a pen core, a center rod inpens, an ink-absorbing materials made of fibers, an ink-storage sponge,a head of brush pen, a brush pen for painting colors, a brush pen formakeup tools, and so forth.

(10) Materials for Medical Supplies or Instruments: artificial bloodvessels, artificial organs, artificial joints, and tube-, thread- orplate-like polymeric materials, and so forth. are exemplified. Forexample, medical supplies which are used by touching to human bodies orhuman organisms (catheters, tubes or other items for draining), bodyfluid absorbing materials, contact lenses, lenses for goggles, bandagesof synthetic fibers, gauze and instillation accessories are given.

(11) Polymeric Materials Composites: the adhesion property of fiberswhich are used in polymer composites or fiber-reinforced plastics isimproved by the present Invention. The obtained fiber is used to producepolymeric materials composites with a high strength.

(12) Synthetic Papers: synthetic papers made of polymic materials, suchas polyolefins (polyethylene, polypropylene, and so forth.), polyestersand so forth,. are whitened by adding air bubbles or fillers, and theyare used as the substitute of papers. The modification of thehydrophilic property of the surface by the present invention can improvean adhesion property and a printing property of synthetic papers.

(13) Materials with Improved Adhesion Property: in addition to themodification of the adhesion property of materials for various uses asdescribed above, the present method can modify the adhesion property ofvarious kinds of polymer films or mold products, and an adhesiveproperty with a homotypic or a different material can be improved.

(14) Application of Hydrophilic Film: the present invention gives a highhydrophilic property to polymer films of polyolefins, polyester, and soforth. For example, as a water-absorption polyester film obtained bythis invention gives a good adhesion property and a wettability towater, the antifog effect is acquired by sticking on glass or a mirror.

(15) Use for Battery Separator: battery Separators produced by themethod of the present invention give not only a high physical strengthbut also high chemical resistances to alkalis and acids. They give alsoa high absorption rate of various kinds of electrolytic solutions and ahigh retention ability of them. Therefore, they can be useful for eachof primary batteries and secondary batteries. They can be used inbatteries with any shapes such as tubes, buttons and flat forms, andused in both of open cells and closed cells when they are secondarybatteries.

As primary batteries, an alkali-manganese battery using an alkalineelectrolytic solution, a mercury cell, a silver oxide cell, an air cell,a silver chloride cell, a lithium battery and a manganese battery usingan acid electrolytic solution, and so forth are exemplified. Assecondary batteries, an alkaline storage battery using an alkalineelectrolytic solution (an Edison battery), a nickel-cadmium battery (aJungner battery), a nickel-hydrogen battery, a lead storage batteryusing an acid electrolytic solution, and so forth are exemplified.Battery separators prepared by the present invention can be used insteadof paper-made battery separators which have been so far used inbatteries.

Best Methods for Carrying Out the Invention EXAMPLE

Although this invention is explained by indicating examples below, thisinvention is not limited to these examples and interpreted. In order toexplain the excellent effect of the present invention, the examples arecompared with comparative examples.

Materials, reagents and tests or evaluation methods used in examples andcomparative examples are given below.

(A) Materials containing polymeric materials

(1) Polymeric materials used in examples and comparative examples arelisted in Table 1. Any manners to remove antioxidants, stabilizers andthe other additives in the materials were not carried out. Abbreviationsfor words used here are given as follows. PP: polypropylene, PE:polyethylene, PET: polyethylene terephthalate, PSU: polysulfone, PP/PEor P/E: a mixture of polypropylene and polyethylene, and HPDE:high-density polyethylene.

(2) Materials for dental treatment : orthodontic brackets (size2.23×3.0×3.8 mm), which are made of polypropylene (each weight: about 31mg) or a nylon 12 (with a weight of about 32 mg) are reinforced withaluminum metal fittings.

(3) As members of writing implements or writing and painting tools formakeup, the following various kinds of materials are used.

-   1) A PP collector with a cross section of a comb-like shape: a    polypropylene-made ink collector with a cross section of a comb-like    shape. This has a structure which is composed of two tubes; one tube    with comb-teeth gives an outside diameter 6 mm and an inside    diameter 2 mm. The other tube is a cylinder with an outside diameter    6 mm and an void diameter 4 mm. It's weight is 0.61 g and the length    is 28 mm. This collector is called as “PP collector 1” in short. Its    shape is shown by FIG. 1.-   2) PP collector made by a laminate of sheet bodies : a    polypropylene-made disc whose center is cored and has an embossed    surface (a number of embosses on a disk is 40) is prepared. A    laminate of several number of the sheet bodies is used as an ink    collector. The distance between each of sheet bodies is given by the    height of the embosses on the disk. The disk gives a weight of    0.055 g. This collector is called as “PP collector 2” in short.-   3) ABS collector with a cross section of a comb-like shape: an ink    collector made of ABS resin (a copolymer of acrylonitrile, butadiene    and styrene) whose crosss section is a comb-like shape. and its    weight is 0.61 g and the length is 28 mm. This collector is called    as “ABS collector 1” in short.-   4) ABS collector made by a laminate of sheet bodies: an ABS    resin-made disc whose center is cored and has an embossed surface (a    number of embosses on a disk is 40) is prepared. A laminate of    several number of the sheet bodies is used as an ink collector. The    distance between each of sheet bodies is given by the height of the    embosses on the disk. The disk gives an outside diameter of 19.8 mm,    an inside diameter of 5.0 mm and a weight of 0.061 g. This collector    is called as “ABS collector 2” in short.-   5) An ink tank: a polypropylene resin-made tube with an outside    diameter from 7 mm (a point side) to 10 mm (an outlet) and an inside    diameter from 2 mm (a point side) to 8 mm (an outlet) and its length    about 8 mm.-   6) A pen core 1: This is made of PET resin. It's length is 37.0 mm,    the outside diameter, 1.8 mm and the weight, 0.188 g. It is made by    fusing a bundle of PET fibers.-   7) A pen core 2: A slim pen core; whose commercial name is “Procky    slim core”. It is made of PET resin. It's length is 27.0 mm, the    outside diameter, 2 mm and the weight, 0.0638 g. It is produced by a    fusion bonding of a bundle of PET fibers.-   8) An ink-guiding core: This is made of PET resin. It's length is    22.5 mm, the outside diameter, 1.8 mm and the weight, 0.050 g. It is    made by a fusion bonding of a bundle of PET fibers.-   9) A brush head of a brush pen 1: this is made of polybutylene    terephthalate (PBT) resin. It's length is 150 mm, an outside    diameter of a bonded portion, 2.0 mm and the weight, 0.302 g. The    brush head is a part for writing of a brush pen and it is used for    writing as retaining ink or sumi-ink in it. Besides, the brush head    is used for brush pen for a makeup. As the brush is made with fine    filament fibers of a synthetic polymer, each fiber surface cannot    give a wettability but it can absorb water, water-soluble ink, or    cosmetic chemicals because of a capillarity.-   10) A brush head of a brush pen 2: this is made of nylon 66 resin.    Its length is 250 mm, an outside diameter of a bonded portion, 5 mm    and the weight, 0.198 g.-   11) Stuffing fiber: it has a structure that PET fibers (a diameter,    2 denier) are stuffed in a tube made of PP film. Its length is 78.0    mm and an outside diameter, 7 mm.-   12) An ink-storing sponge: polyurethane-made sponge. The weight is    16.0 mg and the thickness 2.0 mm. The form is a trapezoid (an upper    side 120 mm, an under side 170 mm and a height 19 mm) which is cut    in a special form.

(B) Reagents

(1) Polyvinylalcohol (PVA): its number-average degree of polymeriztionis 1500-1800.

(2) Sodium carboxymethyl cellulose (CMC)

(3) Acrylic acid

(4) Methacrylic acid

(5) Methyl methacrylate

(6) Sodium persulfate (SPS)

(7) Potassium persulfate (KPS)

(8) N,N′-Azobisisobutylonitrile (AIBN)

(9) Cerium ammonium nitrate (IV) (CAN)

(10) Benzophenone

(11) Methanol

(12) Sodium hydroxide

(13) Hydrochloric acid

(14) Toluene (Impregnant A)

(15) Sodium dodecylbenzene sulfonate (DBS): this was used as asurfactant.

(16) Decahydro naphthalene (a mixture of cis- and trans-isomers)(Impregnant B)

(17) ortho-Hydroxy biphenyl (OHB): o-Hydrobiphenyl (1 g) and sodiumhydroxide (0.2 g), a surfactant (sodium dodecylbenzene sulfonate) weredissolved in water of 200 ml. This solution is called as Impregnant C.Besides, a solution of o-hydroxy biphenyl (0.5 g) in methanol (300 ml)was dispersed in water and used as a carrier (the dispersion isImpregnant D).

(18) Sodium salicylate (SS): sodium salicylate (1 g) was dissolved inwater (100 ml) and 0.5 ml of an aqueous hydrochloric acid solution(concentration, 10% ) was added in it. The obtained solution wasdispersed in water (the dispersin is Impregnant E).

(19) Diphenyl (DP): Diphenyl (2.5 g) and a surfactant (sodiumdodecylbenzene sulfonate, 0.2 g) were mixed in water of 200 ml (thesolution is Impregnant F).

(20) Carriant (a commercial product made by Toho chemical co. Ltd.): Acarrier for the dyeing of polyesters or the other synthetic fibers. Itcontains anionic surfactants of aromatic ethers or similar compounds. Itwas used as a dispersion in water (Carrier 1).

(21) Carrier TW200 (a commercial product made by Nikka chemical co.Ltd.): a carrier for the dyeing of mixed fabrics containing polyestersand wool. It contains methylnaphthalene and the other compounds. It wasused as a dispersion in water (Carrier 2).

(22) An acid dye, Orange G (Color Index name: C. I. Acid Orange 10).

(C) Ozone Treatment: a specimen was put in a hard glass vessel of 2 L or10 L volume (with an inlet and an outlet for gas), which was equippedwith an ozone generator (a product of Mitsubishi Denki Co., Ltd.,OS-IN). Then, ozone was generated by the ozone generator with an ozoneyield of 1 g/hour or an oxygen gas containing an ozone with aconcentration of 20 g/m³, were introduced into the reaction vessel witha flow rate of 800 ml/min for 1-120 minutes. Then, an ozone-free oxygenwas introduced into the reaction vessel for 10 minutes. Theconcentration of ozone was checked by an iodine titration. The extent ofoxidation of a material was checked by an infrared spectroscopy using aspecimen which was scrapped from the surface of the treated material.The change in the absorbance around 1710 cm³¹ ¹ (due to the absorptionby carbonyl groups) or the ratio of it to the absorbance around at 973cm⁻¹ were used for the judgement. The amount of ozone was 1 g/hour inexample if no remarks was given.

(D) Plasma Treatment: a specimen (fabrics, films, and so forth.) wasplaced on a position between two electrodes in a reaction bath of aplasma generator (a Yamato PR 500). After the pressure of the reactionbath was decreased to 0.27 Pa, a mixture of argon and oxygen (a volumeratio, 1:1) was introduced in the reaction bath until the pressure wasincreased to 5.6 Pa. A power supply was from 40 W to 100 W, and a glowdischarge was carried out mainly for from 30 seconds to 3 minutes at anoscillation frequency of 13.56 MHz. After the discharge, theintroduction of a mixture of argon and nitrogen was stopped, thepressure was raised to a normal pressure and the treated specimen wastaken out. The effect of the treatment was judged from a lowering of acontact angle of water to films.

(E) UV irradiation: In order to carry out an active treatment sterp, ahigh pressure mercury lamp (an H400P produced by Toshiba Co., Ltd.) wasirradiated directly to a material from a distance of 10 cm. In order tocarry out a grafting, a reaction mixture was put in a Pylex-glass-madereaction vessel, and a high pressure mercury lamp (an H400P produced byToshiba Co., Ltd.) was irradiated to the reaction vessel from a distanceof 20 cm. In order to obtain a uniform irradiation, the reaction tuberotated itself and is revolved around the UV lamp. The reaction mixturemeans a solution of an initiator and a monomer in a solvent, or a gassuch as air or nitrogen containing monomer vapor.

(F) Evaluation of water absorptivity: measurements of a waterabsorptivity and a rate of water-absorption as described below.

(1) Water absorptivity: a specimen (size 10 cm×10 cm) was put in abeaker containing water, and it was stirred mildly with a glass rod forone minute. Then, the specimen was taken out of the beaker and hung downfor 3 minutes (until water drops were not found). The increase in weightof the specimen (an amount of absorbed water) was estimated by thesubtraction of the weight of the dried specimen from the weight of thewater absorbed specimen. The percentage of a weight of absorbed water tothe dried weight of the specimen gives “water absorptivity”.

Water absorption (%)=(a weight of absorbed water/a weight of driedspecimen)×100.

(2) Water absorption rate: a specimen of 1.5 cm width was hung and theportion of 1.5 cm length from the edge was immersed in water. Thedistance of water risied for one minute was observed (unit, cm/min.).

(G) Measurement of contact angle of water: a contact angle measuringapparatus (the CA-X of Kyowa Kaimen Kagaku Co., Ltd.) was employed. Awater drop of about 1 mm diameter was dropped on a surface of a specimenby an injector at 20° C., and the contact angle was estimated by acalculation from the figure of the water drop enlarged by a videocamera.

(H) Washing fastness test: a specimen was put in an aqueous solution(0.4 wt. %) of a weak-alkaline, fatty acid soap (a commercial name,Powder Soap of Lion Co., Ltd.) with a liquor ratio of 1/250 and it waswashed in the boiling state for 5 minutes with stirring. Then, thespecimen was completely rinsed with water and dried. A water absorption(%), a water absorption rate and a tensile strength were measured andthe values were compared with those before this washing process.

(I) Evaluation of dyeing property : ten orthodontic brackets were put inan aqueous solution of an acid dye, Orange G (100 ml), and an aceticacid was added in the mixture to give the pH=5.0. The dyeing mixture wasboiled for 15 minutes, then the boiling was stopped and it was allowedto stand for 2 hours. The orthodontic brackets were washed in a boilingwater and dried.

(J) Tensile strength test: a specimen was cut in a rectangle (the size,15 mm×70 mm), and it was equipped on a tensile strength tester (aSFV-55-0-20M of Imada Seisakusyo Co., Ltd.) in the way that each part of1 cm width from both edges of the specimen is pinched by the cramps of atensile tester (a SFV-55-0-20M of Imada Seisakusyo Co., Ltd.) and it wasdrawn at a rate of 100 mm/min. Each specimen was drawn along itslengthwise direction or its cross direction. Only the values along thelengthwise direction are given in each of specimens.

(K) Peel strength test of adhesion

(1) film: a test piece was cut in a rectangle with a size of 30 mm(vertical direction)×5 mm (a width). An adhesive 0.1 g is put on thepart of 5 mm width from the edge of the test piece and the test piecewas attached to a plywood board (2 mm in thickness, size 20 mm×10 mm) ora tag paper (0.2 mm in thickness, size 20 mm×10 mm). A weight of 500 gwas put on the test piece attached to the plywood board or the tag papercovered with polyethylene film for 12 hours. Both of a portion of 10 mmwhich was not attached to the plywood and that of the another end whichwas not pasted to the film were pinched by the cramps of the tensiletester (a AGS-H of Shimadzu Seisakusyo Co., Ltd.) and it was drawn bythe tester at a rate of 30 mm/minute. The energy required for thepeeling of the test piece was estimated from the tester. In order tostandardize adhesion conditions, the relative value was calculated bysetting the measured value for the untreated test piece as 1.0 by thesimilar measurement.

Used adhesives were a polycyanoacrylate type adhesive (Aron-alpha, aproduct of Toa Gosei Co., Ltd.) for an adhesion to the plywood board anda stick-type paper use adhesive for stationery (a commercial name: UHFstick produced by Mitsubishi Pencil Co. Ltd.) for an adhesion to the tagpaper.

(2) Orthodontic brackets: about 0.1 g of an adhesive was put on thesurface of treated or untreated brackets. Then, the bracket was attachedto an upper surface of a ceramic plate (size 10 mm×20 mm). A metallicloop wire was connected to the bracket by hanging. The ceramic plate waspinched by an under cramp of a tensile tester (a SV-55-0-20M of ImadaSeisakusyo Co., Ltd.) and the metallic loop wire was pinched by an uppercramp. The specimen mounted on the tensile tester was drawn at a rate of110 mm/min and the stress which was necessary for the peeling theadhesion between the bracket and the ceramic plate was observed. Inorder to standardize the measured tensile strength, the observed valuefor the untreated bracket in the similar measurement was defmed to be1.0 and the peel strength of adhesion was estimated as a relative value.An adhesive containing polymeric methacrylic resin, and so forth whichis used by mixing methyl methacrylate monomer, poly(methyl methacrylate)and catalysts (a commercial name, Super Bond (San Medical Co. Ltd.) or ahomemade polymer solution were used as adhesives.

(3) Ink-absorbing sponge: each part of 5 mm width from the edge of anink-retaining sponge are pinched by the cramps of a tensile tester (aAGS-H of Shimadzu Seisakusyo Co., Ltd.) and it was drawn at a rate of100 mm/min.

(L) Retention of electrolytic solutions: a weight of a dried test piece(size 5 cm×5 cm) was defined as W1. A specimen was dipped into anaqueous potassium hydroxide solution (30 wt. %) for 5 minutes. Thespecimen was taken out of the solution and was hung on for 3 minutes.The weight of the specimen W2 was measured when liquid drops were notseen. The following equation gives the absorption (%) of an electrolyticsolution.Electrolytic solution retention (%)=100×(W2−W1)/W1

(M) Alkali-resistance of battery separators: a weight of a driedspecimen (size 5 cm×5 cm) was given as W1. A specimen was dipped in anaqueous potassium hydroxide solution (30 wt. %) for two weeks at 70° C.The specimen was taken out of the solution and its weight (W2) wasmeasured after hanging for 3 minutes. Then the specimen was washed withwater sufficiently and dried in vacuum, and the weight (W3) wasmeasured. An electrolytic solution (%) and a weight increase (%) wereobtained by the following equations.Electrolytic solution absorption (%)=100×(W2−W1)/W1Weight decrease (%)=100×(W1−W3)/W1

(N) Acid-Resistance of Battery Separators: a weight of a dried specimen(size 5 cm×5 cm) was given as W1. A specimen was dipped in an aqueoussulfuric acid solution (40 wt. %) for two weeks at 70° C. After twoweeks, the specimen was taken out of the solution and was hung on for 3minutes. The weight of the specimen (W2) was observed. Then, thespecimen was washed in water and dried sufficiently, and its weight W3was measured. In addition, its water absorptivity and tensile strengthwere observed. The following equations were used to estimate anabsorption (%) of an acid electrolytic solution and a weight decrease(%).Electrolytic solution absorption (%)=100×(W2−W1)/W1Weight decrease (%)=100×(W1−W3)/W1

(O) Oxidant-resistance test of battery separators: non-woven fabricstreated for battery separators were dipped in an aqueous solution ofhydrogen peroxide (concentration, 40 wt. %) for seven days at 50° C.,Then, the specimens were washed sufficiently in water and dried, and theweight change and tensile strength were measured.

The battery performance test was carried out by the following methods,(P)-(T).

(P) Lowing of capacity of batteries incorporated with battery separatorsin the course of the self discharge: a treated specimen was incorporatedin a sealed nickel-hydrogen battery of a coin-size (a nominal capacity,500 mAh). When the property of the battery seemed to be stable, theywere charged to 120% of the capacity by an electric source of 0.1C(Coulomb). After four cycles of charge-discharge processes, thepercentage of an average value of a residual capacity (C) to theoriginal value for each of batteries was estimated after the test fortwo weeks at 45° C.

(Q) Charge/discharge method for batteries incorporated with batteryseparators: the charge was carried out by charging direct current of 100V into a sealed-type lead storage battery (with six cells) until thevoltage of the battery became 12 V. The discharge was carried out byconnecting the electric terminals to both poles of the battery, andadded a resistance to make the electric current to be 1.20 A or 34 A.

(R) Change in capacity of a battery incorporated with a batteryseparator by the discharge for 5 hours: the time when the terminalvoltage of all cells in the battery changed from 12 V to 10.5 V(1.7V/cell) from the beginning of the discharge (an initial current of1.20 A) was observed.

(S) Change in capacity of batteries after discharge at low temperature:The time (electric discharge persistence time) when the terminal voltageof all cells in the battery changed from 12 V to 6 V (1.0 V/cell) by thedischarge from the beginning of the discharge (an initial current of 35A) was observed at −15° C.

(T) Voltage of a battery incorporated with a battery Separator after adischarge for five seconds: the terminal voltage per one cell in thebattery was observed at 5 seconds after beginning the effectivedischarge at low temperature.

Example 1

Hydrophilic Treatment of Polypropylene Non-woven Fabric by Modification1 A PP non-woven fabric 1 (weight 1.0 g, size 20 cm×20 cm) which wasgiven as Sample 1 in Table 1 was immersed in 100 ml of Impregnant A(tolune) for 10 minutes at 50° C. in order to carry out the impregnationstep. Then, the PP fabric was rinsed with methanol and centrifuged forone minute at a rate of 800 rpm. The increase in weight of the PP fabricwas about 4 wt. %. Then, the PP fabric was treated with ozone for 30minutes in order to carry out the activation process. An IR spectroscopyof the treated or untreated PP fabrics was carried out and the ratio ofthe absorbance at around 1710 cm⁻¹ (which is due to the absorption ofcarbonyl groups) for the treated PP fabric to that of untreated PPfabric was 0.02. Then, the treated PP fabric was put in a vesselcontaining 200 ml of water, 1 g of PVA, 20 mg of cerium ammonium nitrate(IV) and 0.6 ml of acrylic acid, and the UV irradiation was made to thereaction vessel from the distance of 20 cm for 120 minutes at 30° C.After the treatment, the treated PP fabric was washed with a boilingaqueous solution of detergent for 10 minutes and washed with water anddried. The water absorption of the obtained specimen was 310% accordingto the water absorption test. The rate of water-absorption was 2.0cm/min. As the treated PP fabric gave excellent properties in a waterabsorption, a retention of electrolytic solutions, a highalkali-resistance, a high acid-resistance and a high oxidant-resistance,the present modification method is very effective for the preparation ofbattery separators.

Example 2

The same procedure as described in Example 1 was followed, except thatImpregnant B was used as an impregnant, except that a plasma treatmentfor 30 seconds was carried out as an activation process and except thatmethacrylic acid was used as a monomer.

Example 3

The same procedure as described in Example 1 was followed, except thatImpregnant F was used as an impregnant, and except that a UV irradiationfor 60 minutes was carried out as an activation process.

Comparative Examples 1-5

Comparative Example 1 gave the result with untreated specimens of the PPnon-woven fabrics 1 used in Example 1. Comparative Examples 2-5 werecarried out by the same procedure as Example 1, except that one or twoprocesses in Example 1 were omitted.

Example 4

The same procedure as described in Example 1 was followed, except thatImpregnant C was used as an impregnant, and except that a plasmatreatment for 30 minutes was carried out as an activation process.

Comparative Example 6

It gives the result with untreated PP plain fabric.

Comparative Example 7

The same procedure as described in Example 4 was followed, except thatthe impregnation treatment was omitted, and except that 10 mg of AIBNwas used as an initiator of grafting instead of CAN.

Example 5

The same procedure as described in Example 1 was followed, except that aPET non-woven fabric of Sample 4 (a size, 10 cm×10 cm) was used, exceptthat an aqueous dispersion of Carrier 2 (5 g of the reagent was mixedwith 200 ml of water) was used for the impregnation process, except thatan ozone treatment was carried out as the activation process and exceptthat a thermal grafting was carried out at 80° C. using 10 mg of AIBN asan initiator instead of CAN.

Example 6 Grafting in the Gas Phase

An impregnation process of a PET non-woven fabric of Sample 4 (a size,10 cm×10 cm) was carried out in Impregnant A for 5 minutes at 30° C. Asthe activation process, an ozone treatment for 20 minutes was attained.The monomer grafting was carried out as follows; the PET non-wovenfabric treated by the impregnant and activation processes was put in aglass-made reaction vessel. The vessel was evacuated and 0.2 ml of MMAwas put into it. After vaporizing the MMA in the vessel by an evacuationto some extent, a UV irradiation to the reaction vessel was carried outfor 90 minutes. The treated PET non-woven fabric gave a monomer graftingof 5%. It gave good improvements in the adhesion property and the dyeingproperty.

Comparative Examples 8-12

Comparative examples 9-12 were carried out by the same procedure asdescribed in Example 1, except that one or two processes were omitted.

Example 7

A PP/PET non-woven fabric of Sample 3 in Table 1 was used as a specimen.Impregnant C was used for the impregnation step and a plasma treatmentfor 30 minutes was carried out as an activation process. A thermalmonomer grafting was carried out for two hours at 80° C. using amonomer, methyl methacrylate and an initiator, KPS.

Example 8

The same procedure as described in Example 7 was followed, except that aPP/PET non-woven fabric was used as a specimen, and except thatImpregnant E was used for the impregnation step and except that aninitiator, KPS and a monomer, acrylic acid were used.

Comparative Example 13

It gives the result with an untreated PP/PET non-woven fabric.

Example 9

A PET film of Sample 12 was used. The PET film (weight 1.62 g, size 15cm×15 cm) was immersed in 100 ml of an Impregnant E for 15 minutes at70° C. as an impregnation step. Then, the PET film was rinsed withmethanol and the waste of the impregnant was wiped off with a paper anddried for 5 minutes at room temperature. Then, the PET film was treatedby an ozone treatment as an activation process. Subsequently, thetreated PET film was put in a Pyrex glass-made reaction vesselcontaining a solution of 1.2 ml of acrylic acid in 200 ml of water andan UV irradiation to the reaction vessel was carried out for 2 hours at30° C. After the process, the PET film was washed with an aqueoussolution of a detergent for one minute at 60.° C., washed for one minutewith a boiling water, washed with water and dried. The water absorptionof the obtained specimen was 90% and its contact angle of water was63.degree. Its peel strength of the adhesion to a label paper bound witha stick-type paper use adhesive for stationery was 4 when that for anuntreated PET film was 1.

Comparative Examples 14-18

They give the results with untreated PET films and the results obtainedby the same procedure described in Example 9, except that one or twoprocesses were omitted.

Example 10

A HMPE plate of Sample 13 (a weight, 3.84 g and a size, 10 cm×10 cm) wasimmersed in 100 ml of Impregnant B for 15 minutes at 70. ° C. as theimpregnation step. Then, the specimen was rinsed with methanol and thewaste of the impregnant was wiped off with a paper and dried for 5minutes at room temperature. Then, the specimen was made by an ozonetreatment for 30 minutes as the activation step. Subsequently, themonomer grafting by the UV irradiation similar to Example 1 was carriedout using 180 ml of water, 20 mg of CAN and 1.0 ml of acrylic acid.

Comparative Examples 19

It gives the result with an untreated HMPE plate of Sample 13.

Comparative Examples 20-23

They give the results obtained by the same procedure described inExample 10, except that one or two steps were omitted.

Example 11

A PP film of Sample 11 (a weight, 0.38 g and a size, 15 cm×15 cm) wasimmersed in Impregnant C (100 ml ) for 10 minutes at 70. ° C. as animpregnation process. Then, the specimen was rinsed with methanol andthe waste of the impregnant was wiped off with a paper and dried for 5minutes at room temperature. Then, the specimen was made by an plasmatreatment for 30 seconds at 30° C. as the activation step. Subsequently,the monomer grafting by the UV irradiation similar to Example 1 wascarried out using 180 ml of water, 20 mg of AIBN and 1.0 ml of acrylicacid.

Comparative Example 24

It gives the result with untreated PP films.

Comparative Examples 25-28

The same procedure described in Example 11 was followed, except that oneor two processes were omitted.

The above results are summarized in Table 2. In Table 2, the waterabsorption 1 gives the water absorption % of the specimen after theprocesses which were washed with an aqueous detergent solution and waterat room temperature and dried, the water absorption 3 gives the waterabsorption % of the specimen after the treatment steps which wereprocessed by the three times of washing with a boiling aqueous detergentsolution and water and a drying. In Table 2, ozone, plasma andultra-violet light are represented by OZ, PL and UV, respectively. Inthe results in Examples 9-11 and Comparative Examples 14-18, theadhesive used for the measurement of the peel strength of the adhesionis an adhesive containing mainly polycyanoacrylate for Example 10 and

Comparative Examples 19-23, and a stick-type paper use adhesive forstationery was used for the other Examples and Comparative Examples.Example 12

A Method to Give Hydrophilic Property to Carbon Fiber and its Use forComposite

Carbon fiber (6.0 g) of Sample 9 in Table 1 was used as a specimen. Thespecimen was immersed in methanol for 30 minutes at 50° C. as theimpregnation process. Then, the treated specimen was centrifuged for oneminute at a rate of 800 rpm. Then, the specimen was put in a hard glassvessel with 1.5 mm thick. The ozone was regenerated as follows; oxygenwas introduced into an ozone-regenerator with a flow rate of 100 ml/minand ozone with a concentration of 40 mg/L was regenerated. The ozone wasintroduced in the reaction vessel for 30 minutes at 20° C., andsubsequently, ozone-free oxygen was introduced in the vessel for 10 min.Then as the monomer grafting step, the treated specimen was put in aglass-made reaction vessel and acrylic acid 1.2 ml, water 200 ml andmethanol 5 ml were added in it. The same UV irradiation to the reactionvessel as described in Example 1 was carried out for three hours as thegrafting step. Then, the reaction mixture was put in a large amount ofwater. The carbon fiber attached by polymers was taken out of the water.The treated carbon fiber was washed in a boiling aqueous detergentsolution, three times. The grafting was 15%. After drying, the carbonfiber gave the water absorption 200% (that of untreated carbon fiber,60%).

Comparative Example 29

The same procedure as described in Example 12 was followed, except thatthe impregnation process was omitted. The grafting % of the treatedspecimen was 4.2% and its water absorption was 130%.

Comparative Example 30

The same procedure as described in Example 12 was followed, except thatthe activation process was omitted. The grafting % of the treatedspecimen was 3.0% and its water absorption was 110%

Comparative Example 31

The same procedure as described in Example 12 was followed, except onlythe UV irradiation grafting was carried out and the other steps wereomitted. The grafting % of the treated specimen was 1.0% and its waterabsorption was 100%.

Example 13

The carbon fiber processed in Example 12 was mixed with an epoxy resinadhesive and a rod of 5 mm width×5 mm thickness×100 mm length wasprepared by drying the mixture. As a reference, a rod with similar sizeto the above one was made with the epoxy resin adhesive and untreatedcarbon fiber. The tensile strength of the epoxy resin rod reinforced bythe hydrophilic carbon fiber was 40 times larger than that of thereference rod containing untreated carbon fiber.

Example 14

Hydrophilic Treatment of Wool Fiber Fabric

Wool fiber (1.0 g) of Sample 10 in Table 1 was used as a specimen. Thespecimen was immersed in a solution of anhydrous sodium carbonate (10mg) in methanol (10 ml) and water (90 ml) for 30 minutes at 50° C. asthe impregnation step. Then, the treated specimen was centrifuged forone minute at a rate of 800 rpm. Then, the specimen was treated by anozone treatment similarly to Example 12. Then as the grafting step, thetreated specimen was put in a glass-made reaction vessel and acrylicacid 1.2 ml, water 200 ml and methanol 5 ml were added in it. The UVirradiation was carried out to the reaction vessel for two hourssimilarly to Example 12 under an air atmosphere. The wool fiber fabricattached with polymers was take out of the reaction vessel. The treatedspecimen was washed in a boiling aqueous solution of a detergent threetimes. The grafting was 18%. The obtained treated wool fiber fabric gavea water absorption 300%.

Comparative Example 37

The same procedure as described in Example 14 was followed, except thatthe impregnation process was omitted. The grafting percentage of thetreated specimen was 4.2%.

Comparative Example 38

The same procedure as described in Example 14 was followed by carryingout only the monomer grafting step by the UV irradiation, except thatthe other processes were omitted. The grafting percentage of the treatedspecimen was 1.5%.

Comparative Example 39

The same procedure as described in Example 14 was followed, except thatthe activation process was omitted. The grafting percentage of thetreated specimen was 1.6%.

Example 15

Water Absorption Test

Treated or untreated wool fiber fabrics were floated on the surface ofwater, keeping the thin direction of the specimen parallel to thesurface. The time for the specimen absorbed water to sink was observed.The short time indicates a high hydrophilic property. The time observedfor an untreated wool fiber fabric was 60 minutes. The time observed forthe wool fiber fabric treated in Example 14 was one second and thoseobserved for the wool fiber fabrics obtained by Comparative Examples 37,38 and 39 were 15 seconds, 28 seconds and 30 seconds, respectively.

Example 16

Improvement of the Hydrophilic Property of Polypropylene-Made SyntheticPapres

The same procedure as described in Example 2 was followed to treatporous PP films of Sample 14 in Table 1 which were used as syntheticpapers, and their hydrophilic property was improved. It was possible towrite characters with water-soluble ink on the treated synthetic papers.In addition, it was possible to bond label papers to the treatedsynthetic papers with water soluble glues (starch, CMC, PVA glues, andso forth.). As the label paper bond to the treated synthetic paper wasbroken in the tensile strength measurement, its peeling was impossible.

Example 17

Improvement of the Hydrophilic Property of Porous Polyethylene Film andits Application for Filters.

The same procedure as described in Example 9 was followed, except thatporous polyethylene film of Sample 15 in Table 1 was used as thespecimen. The water absorption of the treated PE film was 200% (that foran untreated specimen was 5%). The contact angle of water to the treatedspecimen could not be observed (it seemed to be 0.degree. that of theuntreated specimen 120.degree.) Furthermore, the weight increase in thetreated specimen was 2%. The obtained hydrophilic porous polyethylenefilm gave the alkali-resistance and the acid-resistance, and it wasuseful for the filtration of components contained in water.

Example 18

Improvement of the Hydrophilic Property of Porous Polysulfone Film andits Application for Filters.

The porous polysulfone film of Sample 16 in Table 1 (weight 0.5 g, size10 cm×10 cm) was immersed in an aqueous methanol solution (methanol 10volume %) for one minute at room temperature as the impregnation step.Then, the specimen was treated with ozone for two minutes as theactivation step. The other procedures were carried out in the samemanner as described in Example 17.

The water absorption 3 of the treated polysulfone film was 250% (thatfor a untreated specimen was 5%). The contact angle of water to thetreated film could not be observed because of the high water absorptionproperty (that of the untreated specimen 120.degree.). Furthermore, theweight increase in the treated specimen was 2%. The obtained hydrophilicporous polysulfone film gave the alkali-resistance and theacid-resistance, and a high heat-resistance (it was thermally treatedthree times in an autoclave at 120° C.). The obtained treated porouspolysulfone film useful for the filtration of components contained inwater.

Example 19

Improvement of Hydrophilic Property of PP Non-woven Fabric 2 by“Modification Method 2”.

A PP non-woven fabric 2 (weight 1.0 g and size 15 cm×15 cm) which isgiven as Sample2 in Table 1 was immersed in 100 ml of Impregnant F for 5minutes at 50° C. Then, the fabric was centrifuged at a rate of 1000rpm. When the increase in weight of the PP fabric was 4 wt. %, it wastreated with ozone for 30 minutes at 20° C. in order to carry out theactivation process. Then, the treated specimen was put in a reactionvessel. Furthermore, after 20 ml of water, 60 mg of potassiumpersulfate, 0.3 g of polyvinyl alcohol and 6 ml of methanol were addedin the reaction vessel, the reaction mixture in the vessel was allowedto stand for two hours at 80° C. Then, the specimen was washed withwater and washed with an aqueous solution of a detergent. The waterabsorption 3 of the obtained treated PP non-woven fabric 2 was between800% and 1000%. The weight increase in the specimen after thehydrophilic treatment was not measured within the accuracy of 0.1 mg.The result is given in Table 2. After six times of washings with adetergent, the obtained specimen kept a water absorption of over 810%.The obtained treated specimen was completely applicable for the materialwhich could be used as materials with the water absorptivity.

Example 20

Improvement of Hydrophilic Property of PP Non-woven Fabric 2 by“Modification Method 2”.

The same procedure as Example 19 was followed, except that CMC was usedfor the hydrophilic polymer treatment instead of PVA. The waterabsorption percentage of the treated specimen was 600-900% and the waterabsorption property gave a durability.

Example 21

Application as a Microbial Culture Medium

Each of improved non-woven fabrics obtained by the same procedure asExamples 19 and 20 was cut in two pieces of a size of 2 cm×2 cm, andthey were aligned in a petri dish of 8 cm diameter and 2 cm depthwithout an overlapping. A bouillon/agar solution 100 ml was prepared bydissolving meat extract (191 wt. %), polypeptone (1 wt. %), sodiumchloride (0.5 wt. %) and agar (0.5 wt. %) in water. The agar in themixture was dissolved by using a microwave oven, and a bouillon/agarsolution 50 ml was infiltrated through said non-woven fabrics preparedby the present method. Then, the mixture was cooled down to the roomtemperature. The non-woven fabrics containing the bouillon/agar solutionwere put in the test tubes, which had been autoclaved for 15 minutes at120° C. These test tubes were allowed to stand at 37° C. overnight. Thefollowing day, after confirming the asepsis,. microbes (Escherichia coliK-12 strain, Salmonella Typhirnurium LT-2 strain and Bacillus subtilisMarburg strain, and so forth.) were planted on the fabrics, and theywere cultivated overnight at 30-37° C. A microscopic observation showedthat each of the microbes was growing well.

Comparative Example 40

The same procedure as described in Example 19 was followed, except thatthe impregnation process was omitted. The water absorption percentage of780% of the treated specimen decreased to 400% after three times ofwashings with an aqueous detergent solution.

Example 22

Improvement of Hydrophilic Property of Sample 6 by “Modification Method3” and its Application for Cleansing/Wiping Cloth

A polypropylene/polyester sheath-core type conjugated fiber, PP/PEnon-woven fabric (2.4 g) which is given as Sample 6 in Table 1 wasimmersed in 10 ml of Impregnant D for 10 minutes at 30° C. as theimpregnation step. Then, the fabric was centrifuged (a rotation rate,1000 rpm) until the extent that the surface looked dry apparently. Theweight increase in the specimen after the step was about 4%. Then, thespecimen was treated with ozone for 30 minutes. Then, the ozone-treatedspecimen was put in an Erlenmeyer flask, and 5 ml of methanol, 100 ml ofwater, PVA (0.5 g) and potassium persulfate (0.1 g) were added in theflask and the flask was allowed to stand for 2 hours at 80° C. Afterthis treatment, the specimen was washed sufficiently with water at 60°C. Then, after squeezing water, the treated no-woven fabric was put in avessel together with water (400 ml), CAN (10 mg) and acrylic acid (5ml). The reaction mixture was allowed to stand for 2 hours at 80° C.under air atmosphere. After the treatment, the treated fabric was washedwith an aqueous solution of a detergent at 60° C., three times (500 mlof water was used in each washing). After drying the treated specimen,it gave a water absorption of 2310%. That of an untreated non-wovenfabric was 350%. The weight increase in the specimen by the hydrophilictreatment was 4%. The present modification method gave higher waterabsorption (%) and faster water-absorption rate and more durable waterabsorption property than the procedure by “Modification 1” (Modificationmethod 1 gave about 1400% for the same specimen as used here), and thetreated specimen was useful for the cleansing/wiper application. Afterabsorbing water to the treated non-woven fabrics (water absorption,about 2000%), ten pieces of the treated non-woven fabrics weresuperposed. The superposed non-woven fabrics were mounted on a cleansingmop and the mop was used to clean a wooden floor. After using it, it wasrinsed with water and used repeatedly. It could be used over ten times.

Example 23

Hydrophilic Treatment of PP Non-woven Fabric 2 and an Application forDisposable Sanitary Supplies.

A model of disposable diaper was prepared as follows: the hydrophilicpolyolefin non-woven fabric obtained by the procedure of Example 19 wasused for an inside cloth, an untreated hydrophobic polyolefin non-wovenfabric was used for the outside cloth, and a water retention agent(water-absorption polymers; pulp, starch or polyacrylic acid and itsderivatives, and so forth.) was used as a core material. Namely, anuntreated hydrophobic polypropylene non-woven fabric was put on thebottom, and a water retention polymer was put on it, and the hydrophilicpolyolefin non-woven fabric 2 of the present invention was put on thetop. When water was poured on the diaper model, water was penetratedquickly through the hydrophilic polyolefin non-woven fabric 2 andabsorbed by the water retention agent. Thus, the non-woven fabricimproved in the water absorption property prepared by the presentinvention was available preferably for the material for disposablediapers and sanitary materials or sanitary protections.

Example 24

Improvement of Adhesion Property of a Dentition Orthodontic Appliance

MMA was grafted to 20 pieces of polypropylene-made orthodontic brackets(0.622 g) by the same procedure as described in Example 6.Polymerization inhibitors contained in MMA were removed before use. Thetreated brackets gave a good adhesion property in the adhesion toceramic materials for the dentition with a polymerizable acrylic resinadhesive, and the breakdown of the bracket bonded to the ceramics wasobserved in the peel strength test. In addition, the orthodonticbrackets made of nylon 12 and the other polymers gave the same resultsas those described above. After dipping the modified brackets which werebonded to the ceramic materials in water for one year at 30° C., theloweing in the adhesion force between them was not observed. Bothbrackets of PP and nylon 12 which were modified by the present inventionwere not dyed with an acid dye (Orange G) in the dyeing test.

Comparative Example 41

PP/PE non-woven fabrics modified by the hydrophilic treatment withwell-known surfactants (the non-woven fabrics produced by Japan Vileneco. Ltd. were impregnated with surfactants) were prepared and the sametests as Example 1 were carried out. The results are given below.

-   1) Alkali-resistance test: the water absorption property of the    treated fabric decreased to the original value of the untreated    fabric, 5%.-   2) Acid-resistance test: after washing sufficiently with water, the    water absorption property of the treated fabric decreased to the    original value f of the untreated fabric, 5%.-   3) Oxidant-resistance test: after washing sufficiently with water    and drying, the water absorption property of the treated fabric    decreased to the original value of the untreated fabric, 5%.

Comparative Example 42

Grafting of Acrylic Acid to PP Non-woven Fabric 1 by a Well-known UVIrradiation.

PP non-woven fabric1 (weight 1.2 g and size 7.7 cm×10 cm) was put in areaction mixture containing acrylic acid monomer 20.0%, water 78.8%,benzophenone 0.2% and methanol 1.0% (each % represents weight %), andthe reaction mixture was made by the UV irradiation for two hours. Afterthe reaction, the product was jelled with resulted polymers, but whenthe product was washed with a boiling aqueous solution of a soap, asodium salt of a fatty acid for 10 minutes and water, the specimen wasseparated from the polymers dissolved in the washing process. The waterabsorption percentage of the treated non-woven fabric was 100% (that ofthe untreated non-woven fabric was 48%). Its grafting percentage was 1%.Namely, the grafting by the UV irradiation to the present non-wovenfabric seemed to be difficult, and the polymer composed of only acrylicacids which was formed seemed to be dissolved and removed from thefabric by washing with a boiling aqueous detergent solution. The waterabsorption of the treated no-woven fabric was decreased by the treatmentwith acids or alkalis.

Examples for writing materials are described below.

Writing Implement Example 1

Hydrophilic Treatment of PP Collector 1 by Modification 1.

The 40 pieces of PP collector 1 were immersed in 200 ml of Impregnant Dfor 5 minutes at 50° C. in order to carry out the impregnation step.Then, the collectors were rinsed with methanol and centrifuged for twominutes at a rate of 1000 rpm. The impregnant impregnated in thecollectors was about 2% in weight. Then, the PP fabric was treated withozone for 30 minutes as the activation process. The IR spectroscopy ofthe surface of the treated collectors was carried out and the ratio ofthe absorbance at around 1710 cm⁻¹ (which is due to the absorption bycarbonyl groups) to that at around 973 cm⁻¹ was 0.02. Then, the treatedcollectors were put in a Pyrex-glass vessel containing 200 ml of water,10 ml of acrylic acid and 100 mg of potassium persulfate. After puttinga cover on the vessel, The UV irradiation was made to the reactionvessel for two hours. The treated collectors were taken out of thereaction mixture and was washed in a aqueous solution of a detergent for10 minutes at 60° C. and washed with water and dried. The collectorsimproved in the hydrophilic property were obtained. The obtainedimproved collectors were reversed. The portion of a distance of 3 mmfrom the end of the collector was immersed in water or an aqueouswater-soluble ink solution. The water or the ink solution went up to thetop of the collector in 10-20 seconds, while untreated collectors gaveno ascent of water or the ink solution in the same test as describedabove. The collectors obtained by the present process were easily wettedwith water and their contact angle of water was below 5.degree. On theother hand, the untreated collectors were not wetted with water whenthey were immersed in water and their contact angle of water was about100.degree.

Writing Implement Example 2

200 pieces of PP collector 2 were immersed in Impregnant B for 5 minutesat 50° C. After this process, the same procedure as described in WritingImplement Example 1 was followed, except that methacrylic acid was usedas a monomer instead of acrylic acid. The obtained modified PPcollectors 2 gave a good wettability to water and their contact angle ofwater was below 5.degree. They were wetted well with water-soluble inksand gave the property preferable for ink collectors. On the other hand,the untreated PP collector 2 was not wetted with water when they wereimmersed in water and their contact angle of water was about 100.degree.

Writing Implement Example 3

ABS collector 1 and ABS collector 2 were used. Their impregnationprocess was carried out using Impregnant A at 20° C. After this process,the same procedure as described in EXAMPLE 1 FOR WRITING MATERIALS 1 wasfollowed. The grafting % of acrylic acid of the treated collectors was0.1-0.2%. Their wettablity to water or water-soluble inks was completelyimproved. Their contact angle of water was below 5.degree. The contactangle of untreated collectors to water was about 80-90.degree.

Writing Implement Example 4

The performance test of the PP collectors 1 obtained by the method ofWriting Implement Example 1 was carried out. A pen point 5 made ofpolyester was connected to the hydrophilic PP collector 1 and an inktank chamber made of polypropylene was mounted on them. FIG. 1 gives thestructure in which a PP collector 1, an ink tank chamber 2 and a pencore 3 were set up.

In the collector1, the slit width between the farthest tooth of the combfrom the pen nib is located at L1=3.5 cm, the slit width between allteeth which are located over L2=2.7 cm is 0.15 mm, the slit widthbetween all teeth located in the range of L2=2.7 cm and L3=2.2 cm is0.22 mm and the slit width between all teeth located within L3=2.2 cmfrom the pen point is 0.25 mm. The portion between the collector 1 andthe ink tank chamber 2 was comparted by a barrier material which has alot of air-displacement voids whose size was smaller than any slitsbetween the teeth of the comb structure. The pen core 3 which ispenetrated to the collector dives further in the ink tank in adirect-liquid type pen. Then, the ink tank was filled with the ink 4which contains water as a main solvent and has a surface tension anddensity adjusted to be about 40 mnN/m and 1.08 g/ml at 25° C.,respectively. Thus, a direct-liquid type pen containing the ink 4 wasprepared.

When the nib 5 of the pen prepared in this way was oriented downwardly,the outer pressure was gradually lowered and all of the slits in theteeth of the comb of the collector 4 were filled with the ink 4. In theprocess that all of the slits in the teeth of the comb of the collector4 were filled with the ink 4, any leak of the ink from the pen nib wasnot observed. In addition, the ink 4 stored in all of the slits in theteeth of the comb of the collector 4 did not leak from the pen nib 5,keeping the state of the ink retaining. After that, in the course thatthe outer pressure was gradually increased, all of the ink 4 stored inthe collector 1 returned to the ink tank 2. Thus, the ink collectorworked well as a temporary ink retaining body. Similarly to the abovemanners, a hydrophilic ABS collector 1 which had been obtained inWriting Implement Example 3 was mounted between a polypropylene-made inktank chamber and a pen nib. When the writing test was carried out, thisink collector worked well.

Writing Implement Example 5

Using the hydrophilic ink collector 1 which had been prepared by thesame procedure as described in Writing Implement Example 1, an ink whichcontained ethyleneglycol monoether as a main solvent and has a surfacetension and density adjusted to be about 38.5 mN/m and about 1.03 g/mlat 25° C., respectively was filled in the ink tank by the same mannersas described in Writing Implement Example 4. Thus, a direct-liquid typewriting pen filled with the ink was prepared.

The pen nib of the writing pen prepared in this way was orienteddownwardly and the outer pressure was gradually lowered and all of theslits in the teeth of the comb of the collector were filled with theink. In the process that all of the slits in the teeth of the comb ofthe collector were filled with the ink, any leak of the ink from the penpoint was not observed. In addition, the ink saved in all of the slitsin the teeth of the comb of the collector did not leak from the pen nib,keeping the state of the ink storing. After that, in the course that theouter pressure was gradually increased, all of the ink saved in thecollector returned to the ink tank. Thus, the ink collector worked wellas a temporary ink retaining body.

Writing Implement Example 6

A hydrophilic PP collector 2 obtained by the Modification 1 was mountedbetween a PP-made ink tank chamber and a PET-made pen nib. The mechanismwas similar to FIG. 1, but the collector structure was made by a stackof disks. In this collector with sheet bodies, the farthest disk fromthe pen point is located at L1=3.0 cm, the slit width between the sheetbodies which are located at over L2=2.5 cm is 0.20 mm, and the slitwidth between the sheet bodies which are located within L3=2.5 cm fromthe pen nib is 0.25 mm. The portion between the sheet bodies and the inktank chamber was comparted by a barrier material which has a lot ofair-displacement voids whose size was smaller than any slits between thedisks. The pen core which is penetrated to the collector dives furtherin the ink tank in a direct-liquid type pen Then, the ink tank wasfilled with the ink 4 which contains water as a main solvent and has asurface tension and density adjusted to be about 35 mN/m and about 1.08g/ml at 25° C., respectively. Thus, a direct-liquid type pen containingthe ink was prepared. The direct-liquid type writing pen prepared inthis way gave no leak of ink when the outer pressure was changed in thewriting test and the ink collector worked well.

Writing Materials Example 7

An ABS collector made by sheet bodies obtained by the treatment ofExample 2 was mounted between a PP-made ink tank chamber and a PET-madepen point. In this collector, the farthest disk from the pen point islocated at L1=5.0 cm, and the distance of slits between all sheet bodieslocated in the range L2=4.0 cm is 0.10 mm, and the slit width betweenthe sheet bodies which are located within L2-L3=4.0−3.5 cm from the pennib is 0.15 mm, and the slit width between the sheet bodies which arelocated within L3=3.5 cm from the pen nib is 0.18 mm. The portionbetween the collector and the ink tank chamber was comparted by abarrier material which has air-displacement voids whose size was smallerthan any slits between the sheet bodies. The pen core which ispenetrated to the collector dives further in the ink tank in adirect-liquid type pen. Then, the ink tank was filled with the ink whichcontained water as a main solvent and has a surface tension and densityadjusted to be about 35 mN/m and about 1.08 g/ml at 25° C.,respectively. Thus, a direct-liquid type writing pen containing the inkwas prepared. The direct-liquid type writing pen prepared in this waygave no leak of ink when the outer pressure was changed in the writingtest and the ink collector worked well as a temporary ink retainingbody.

Writing Implement Comparative Example 1

According to the same way as described in Writing Implement Example 5,an untreated PP collector 1 was mounted between a PP-made ink tankchamber and a PET-made pen nib and a direct-liquid type writing pen wasprepared. In the course of storing the ink into the ink collector, whenthe pen nib of the writing pen was oriented downwardly and the outerpressure was gradually lowered, the ink leaked from the nib and thecollector did not work well.

Writing Implement Comparative Example 2

Using an untreated PP collector 2, the same test as described in WritingImplement Comparative Example 1 was carried out. The ink leaked from thepen nib and the collector did not work well.

Writing Implement Comparative Example 3

Using a PP collector 1 prepared by a well-known plasma treatment, thesame test as described in Writing Implement Comparative Example 1 wascarried out. The ink leaked from the pen point and the collector did notwork well.

Writing Implement Comparative Example 4

Using an untreated ABS collector 2, the same test as described inWriting Implement Comparative Example 1 was carried out. The ink leakedfrom the pen point and the collector did not work well.

Writing Implement Example 8

Hydrophilic treatment of PP-Made Ink Tank by Modification Method 1.

Ten PP-made ink tanks were immersed in 200 ml of an aqueous Carrier 2 (5g) solution for 5 minutes at 70° C. in order to carry out theimpregnation step. Then, The treated specimens were centrifuged for oneminute at a rotation rate of 1000 rpm. The impregnant seemed to becontained 2 wt. % in the treated specimens. Then, the specimens weretreated by a plasma treatment for 1 minute in order to carry out theactivation step. Then, the treated specimens were put in a Pyrexglass-made reaction vessel together with 120 ml of water, 10 mg of AIBNand 8 ml of methacrylic acid. After the reaction vessel was covered, theUV irradiation was made from the distance of 20 cm to the reactionvessel for two hours at 30° C. The treated ink tanks were taken out ofthe reaction vessel and washed with an aqueous detergent solution for 10minutes at 60° C. and washed with water and dried.

(Evaluation)

When water or water-soluble ink were put into the obtained ink tank, theinner wall of the tank was wetted well by them. On the other hand, theuntreated ink tank was not wetted at all by water or water-soluble ink,and when the untreated ink tank containing water or water-soluble inkwas shaken, water or water-soluble ink went out of the tank easily. Thecontact angle of water was 10-30.degree for the treated ink tanks andthat for untreated PET-made ink tanks was averagely 100.degree.

Writing Implement Example 9

Surface Treatment of a Pen Core and an Ink-Guiding Core by ModificationMethod 2.

PET-made pen cores 1 (10 pieces), pen-cores 2 (10 pieces) andink-guiding cores (20 pieces) were immersed in 200 ml of Impregnant Afor 5 minutes at 20° C. in order to carry out the impregnation step.Then, the treated specimens were rinsed with methanol centrifuged fortwo minutes at a rotation rate of 1000 rpm. The impregnant seemed to becontained 4 wt. % in the treated specimens. Then, the UV irradiation wasmade to the specimens as the activation step. Then, the specimens weredipped in an aqueous CMC solution (concentration, 10 g/L) for one hourat 80° C. and then for two hours at 40° C. The pen cores and ink-guidingcores were taken out of the reaction mixture and washed with an aqueousdetergent solution for 10 minutes at boiling point, and washed withwater and dried. The water absorption test was carried out for thetreated specimens, untreated specimens and the specimens treated withsurfactants.

(Evaluation) Untreated specimens, the specimens made by the well-knownsurfactant treatment and the specimens treated by the present inventionwere dipped in water for one minute, and the water absorbed in thespecimens were squeezed and the weight increase (water absorption %) wasobserved. In addition, the water absorption percentages for untreatedpen core 1, untreated pen core 2 and untreated ink-guiding core were27%, 43% and 21%, respectively. All of the results for the treatedspecimens gave the improvement as follows; the water absorption for thetreated pen core 1 was 176%, that for the treated pen core, 160% andthat for the treated ink- guiding core, 61%, Actually, the pensassembled with the pen cores and ink- guiding cores treated by themethod of the present invention gave an excellent ink-guiding propertyin the real writing test.

Writing Implement Comparative Example 5

The evaluation test for the water absorption was carried out with thepen cores and ink-guiding cores treated by surfactants. Although theinitial water absorption percentage of the materials treated bysurfactants was high, their water absorption property was decreasedrapidly when they were washed with water at 70° C. (a process that thesamples were washed with water for 5 minutes at about 70° C. with aliquor ratio of 1/100, rinsed with water and dried). Thus, thewell-known surfactant treatment seemed not to be available.

Pen cores 1 treated by a surfactant; initial water absorption 70% andwater absorption after washing 27%.

Pen cores 2 treated by a surfactant; initial water absorption 43% andwater absorption after washing 24%.

Ink-guiding cores treated by a surfactant; initial water absorption 56%and water absorption after washing 21%.

Writing Implement Example 10

Surface Treatment of Brush Heads for a Brush Pen by Modification Method3 Brush heads 1 (10 pieces) and brush heads 2 (30 pieces) were washedwith methanol and dried. Then, the specimens were immersed in 200 ml ofImpregnant D for 5 minutes. Then, the treated specimens were rinsed withmethanol and centrifuged for one minute at a rotation rate of 1000 rpm.The impregnant seemed to be contained 4 wt. % in the treated specimens.Then the ozone treatment was made to the specimens for 20 minutes. Theformation of the carbonyl groups in the treated specimens was notobserved well by IR spectroscopy. Then, the treated brush heads weredipped in an aqueous CMC solution (100 ml) for one hour at 80° C. Then,the specimens were washed with water at 60° C. Then, the treatedspecimens were put in a reaction vessel containing water (120 ml),acrylic acid (6 ml) and AIBN (80 mg), and the reaction vessel was sealedwith a cover and allowed to stand for 2 hours at 80° C. The specimenswere taken out of the reaction mixture and washed with an aqueousdetergent solution for 10 minutes at 60° C., washed with water anddried. The real water absorption test was carried out with the treatedmaterials, untreated materials and materials treated by the well-knownmethod with a surfactant.

(Evaluation) Untreated brush heads and the brush heads treated by thepresent method were put on a surface of water, and the time when thespecimens were sunk in the water was observed. The material which iseasily wettable gives shorter time in this observation. The results wereas follows:

A brush head 1 (PBT resin-made): untreated materials=7 seconds 08, thematerial treated by the present method=1 second 68,

A brush head 2 (nylon-made): untreated materials=11 seconds 05, thematerial treated by the present method=2 seconds 08,

The brush heads treated by the present method gave an excellentink-retaining property and an excellent durability as compared withuntreated ones or treated ones with a surfactant.

Writing Implement Comparative Example 11

Surface Treatment of PET Fiber Stuffing for Ink-Absorbing Use byModification Method 1

The PET fiber stuffing for the ink-retaining use (39.7 g) was taken outof the tubes which holded it and washed sufficiently with water at 50°C., rinsed with water and dried. After drying, the PET fiber stuffinggave no wettability. Then, the specimen was dipped in a mixture oftoluene (10 ml) with methanol (90 ml) for 5 minutes at 20° C. as theimpregnation step. Then, the specimen was centrifuged for one minute ata rotation rate of 1000 rpm. Then, the same procedure as described inWriting Implement Example 1 was followed. The specimen was taken out ofthe reaction mixture and washed with a boiling aqueous detergentsolution for 10 minutes, washed with water and dried. The real waterabsorption test was carried out with the treated material, untreatedmaterial and material treated by a surfactant.

(Evaluation) Untreated material (whose surfactant contained was removedby washing) and the material treated by the present method were put on asurface of water, and the time when the specimens were sunk in the waterwas observed. The untreated material did not sink in the water evenafter two hours. The material treated by the present method absorbedwater and sank in the water in 15 seconds 31. The material treated bythe present method gave really a good water soluble-ink retainingproperty.

Writing Implement Comparative Example 12

Treatment of Polyurethane-made Ink-Retaining Sponge by ModificationMethod 3

The improvement of hydrophilic property of polyurethane-made ink-holdingsponge was carried out by the same procedure as described in WritingImplement Example 10. The water absorption test was made by theobservation of the time when the specimens were sunk in the water. Thepolyurethane-made ink-retaining sponge treated by the present methodsank in the water in 7 seconds and 46. The untreated polyurethane-madeink-retaining sponge did not sink in the water even after two hours. Thewater absorption property of the treated specimen gave a durable waterabsorption property after 5 times washing with a detergent solution.

In addition, the use of each or mixture of Impregnants A, B, C, D and For Carriers 1 and 2 were effective for the hydrophilic treatmentsimilarly to the above result.

Writing Implement Comparative Materials 6

The polyurethane-made ink-retaining sponge treated by a well-knownplasma treatment did not give a good water absorption property and itsdurability as described above.

Writing Implement Comparative Example 7

The ink absorption property of the polyurethane-made ink-retainingsponge prepared by a well-known surfactant impregnation method wascompletely lost only by washing with water.

Writing Implement Example 13

Hydrophilic Treatment of Brush Heads 1 and 2 for a Brush Pen byModification Method 2

Brush heads 1 (10 pieces) and brush heads 2 (10 pieces) were immersed in200 ml of Impregnant B for 5 minutes. Then, the liquid contained in thetreated specimens were removed by a centrifuge separator. When theweight increase in the specimens treated with the impregnant became tobe 4 wt. % of the treated specimens, the ozone treatment was made to thespecimens for 30 minutes at 20° C. as the activation step. Then, thetreated specimens were put in a reaction vessel, in which a mixture ofwater (200 ml), KPS (60 mg), PVA (0.3 g) and methanol (6 ml) were added,and the reaction vessel was allowed to stand for 2 hours at 80° C. inorder to carry out the hydrophilic polymer treatment step. After thetreatment, the specimens were washed with water and an aqueous detergentsolution and dried. The treated specimens gave the water absorptionpercentage, 500-600% and the weight increase in the specimens by thepresent hydrophilic treatment was 0.1%. The water absorption percentageof the specimens was not changed by three times of washing with anaqueous detergent solution.

(Evaluation) Untreated brush heads and the brush heads treated by thepresent method were laid on a surface of water, and the time where thespecimens sank in the water was observed. The results were as follows:

A brush head 1 (PBT resin-made): untreated implements=7 seconds 08, theimplement treated by the present method=1 second 78,

A brush head 2 (nylon-made): untreated implements=11 seconds 05, theimplement treated by the present method=3 seconds 43,

The brush heads treated by the present method gave an excellentink-retaining property and its durability when they were used for a realwriting test.

Writing Implement Example 14

Surface Treatment of PET Stuffing Fiber for Ink-absorbing Use byModification Method 1

The PET stuffing fiber for ink-retaining use (39.7 g) was washedsufficiently with water at 50° C., rinsed with water and dried. Afterdrying, the PET stuffing fiber gave no wettability. Then, the specimenwas dipped in a mixture of toluene (10 ml) with methanol (90 ml) for 5minutes at 20° C. as the impregnation process. Then, the liquidcontained in the treated specimens were removed for one minute by acentrifuge separator. The treated specimen seemed to contain theimpregnant of 4% of the weight. Then the specimens were treated by theozone treatment for 30 minutes. As the specimens were polyester, theobservation of carbonyl groups by IR spectroscopy was difficult. Then,the treated specimens were put in a reaction vessel, in which a mixtureof water (200 ml), KPS (60 mg), PVA (0.3 g) and methanol (6 ml) wereadded, and the reaction vessel was allowed to stand for 2 hours at 80°C. in order to carry out the hydrophilic polymer treatment step.

Then, as the grafting step, the treated specimens were put in a Pyrexglass-made reaction vessel together with a mixture of water (120 ml),methacrylic acid (5 ml) and AIBN (80 mg), and the reaction vessel wassealed with a cover and was allowed to stand for 2 hours at 80° C. inorder to carry out the thermal polymerization. After the treatment, thespecimens were taken out of the vessel and washed with an aqueousdetergent solution for 10 minutes at 60° C. and water, and dried. Thus,the hydrophilic specimens were obtained. The real water absorption testwas carried out with the materials obtained in this way, the untreatedmaterials and the materials treated by a surfactant.

(Evaluation) Untreated material (of which surfactant was removed bywashing) and the material treated by the present method were put on asurface of water, and the time when the specimens sank in the water wasobserved. The untreated material did not sink in the water even aftertwo hours. The material treated by the present method absorbed water andsank in the water in 12 seconds 1. In addition, the material treatedonly by a plasma treatment did not give an effective result. Thematerial treated by the present method gave really a good watersoluble-ink retaining property.

Examples and comparative examples for the battery separator use aredescribed below.

Battery Separator Example 1

Treatment of PP/PE Non-woven Fabric (Sample 3) by Modification Method 1

The PP/PE non-woven fabrics (Sample 3) given in Table 1 were immersed inImpregnant A for 5 minutes at 20° C. in order to carry out theimpregnation step. Then, the collectors were rinsed with methanol andcentrifuged for two minutes at a rate of 1000 rpm. The impregnantcontained in the specimens was about 2% in weight. Then, the specimenswere processed by a plasma treatment for 30 seconds as the activationstep. Then, the treated specimens were put in a cylindrical reactionvessel, and water (150 ml), potassium persulfate (100 mg) and acrylicacid and (10 ml) were put in the vessel. The UV irradiation was made tothe reaction vessel for two hours at 30° C. The obtained fabrics werewashed in a boiling aqueous solution of a detergent for 10 minutes andwashed with water and dried. The water absorption percentage of theuntreated fabrics was 5%, while that of the treated fabrics was 650%.The rate of water-absorption observed for the obtained fabrics was 7.0cm/ minute and that of the untreated fabrics was 0 cm/minute. Theresults of the evaluation of the chemical resistance of the obtainedfabrics required for the battery separator use are described below.

-   1) Washing Fastness Test 1: the obtained specimens were examined by    Washing Fastness Test. After drying, the water absorption percentage    of the specimens was 580%, the rate of water absorption was 6.5 cm,    which gave a decrease of about 10%.-   2) Alkali-resistance Test: no decrease in the tensile strength of    the obtained specimens was observed.-   3) Acid-resistance test: no decrease in the tensile strength of the    obtained specimens was observed.-   4) Oxidant-resistance test: No decrease in the tensile strength of    the obtained specimens was observed.

Battery Separator Comparative Example 1

An well-known nylon non-woven fabric for an alkali battery separator(FT-680N made by Japan Vilene Co. Ltd.) was prepared and examined by thesame test as described in Example for writing materials 1. 1)Alkali-resistance test: after washing with water and drying, the waterabsorption percentage of the nylon separator decreased to 70% of theoriginal value. 2) Acid-resistance test: after drying, the waterabsorption percentage of the nylon separator decreased to 60% of theoriginal value. Its tensile strength decreased to 70% of the originalvalue. 3) Oxidant-resistance test: after drying, the water absorptionpercentage of the nylon separator decreased to 60% of the originalvalue. Its tensile strength decreased to 70% of the original value.

Battery Separator Example 2

The same procedure as described in Battery Separator Example 1 wasfollowed, except that the PP non-woven fabric, Sample 1 in Table 1 wasused and except that the ozone treatment for 30 minutes at 20° C. wascarried out as the activation step.

Battery Separator Example 3

Treatment of PP non-woven fabric 3 by Modification Method 3 and itsapplication for the lead-storage battery.

Ten sheets (weight 22 g) of PP non-woven fabric 3 (Sample 7: size 44mm×145 mm) were immersed in Impregnant B for 5 minutes at 20° C. as theimpregnation step. Then, the UV irradiation was carried out to thespecimens for 20 minutes as the activation step (the distance betweenthe UV lamp and the specimens was 10 cm, and both surfaces of eachfabric were irradiated by IV). Then, the specimens were put in astainless-steel made reaction box, in which methanol (40 ml), water (500ml), PVA (8.0 g) and AIBN (40 mg) were put and the reaction mixture wasallowed to stand for one hour at 80° C. After the treatment, thespecimens were washed sufficiently with water at 60° C. Then, in orderto carry out the grafting step, the specimens were put in a reactionvessel, in which methanol (20 ml), CAN (20 mg), water (500 ml) andacrylic acid (20 ml) were put, and the reaction mixture was allowed tostand for two hours at 70° C. The obtained fabrics were washed with aboiling soap (sodium salt of fatty acid) solution for 5 minutes andwashed sufficiently with water and dried. The weight increase in thefabrics by the grafting was 4%. The water absorption obtained by thewater absorption test for the treated fabrics was 770% and the tensilestrength of the treated fabrics was 1.6 kg. The tensile strength of theuntreated fabric corresponding to that used here was 1.68 kg. Thechemical resistance of the fabrics necessary for the battery separatoruse was evaluated as follows. 1) Alkali-resistance test: the tensilestrength of the obtained treated fabric was 1.42 kg. 2) Sulfuricacid-resistance test: the tensile strength of the obtained treatedfabric was 1.42 kg. 3) Oxidant-resistance test: after drying, the waterabsorption of obtained treated fabric was 770%. Its tensile strength was1.42 kg. The specimens treated by the present method gave good resultsin an absorption property of electrolytic solution, an acid-resistance,an oxidant-resistance and an alkali-resistance. They were preferable forthe battery separator.

Battery Separator Comparative Example 2

A PP/PE non-woven fabric which was treated by the well-known hydrophilictreatment with a surfactant (the fabric FT-310 made by Japan Vilene Co.Ltd. impregnated with surfactants; the unit weight was similar to thatof PP non-woven fabric in Table 1) was prepared and used as a batteryseparator. The results for the evaluation examined by the same test asdescribed in Example for battery separators 1 are as follows. 1)Alkali-resistance test: after washing with water and drying, the waterabsorption percentage of the separator decreased to 10% of the originalvalue. 2) Acid-resistance test: after sufficient washing with water anddrying, the water absorption percentage of the separator decreased to 5%of the original value. 3) Oxidant-resistance test: after drying, thewater absorption percentage of the separator decreased to 5% of theoriginal value. Its tensile strength decreased to 40% of the originalvalue.

Battery Separator Example 4

Treatment of PP Non-woven fabric 1 by Modification Method 2

The PP non-woven fabric 1 (weight 67.5 g and size 27cm×500cm), Sample 1in Table 1 was immersed in 500 ml of Impregnant A for 10 minutes at 50°C. as the impregnation step. The specimen was centrifuged in the sameprocedure as Example for battery separator 1. Then, the specimen wasmade by the ozone treatment for 30 minutes. Then, the treated fabric wasput in an Erlenmeyer flask, and methanol (200 ml), water (500 ml), PVA(6.25 g) and potassium persulfate (1.14 g) were put in the flask. Theflask was allowed to stand for two hours at 80° C. After this process,the specimen was washed with a water for 10 minutes at 60° C., a boilingaqueous detergent solution and washed with water, and dried. The waterabsorption obtained by the water absorption test for the treatedspecimen was 180% and the water absorption rate was 3.5 cm/minute. Thatof the untreated fabric corresponding to the treated specimen was 0cm/minute. In the alkali-resistance test, the acid-resistance test andthe oxidant-resistance test, the decrease in the tensile strength of theobtained treated specimen was not observed.

Battery Separator Example 5

Treatment of PP Non-woven Fabric 2 by Modification Method 3 and itsApplication for the Alkali Battery and its Performance Evaluation

The PP non-woven fabric 2 (weight 63 g), Sample 2 in Table 1 (size 18cm×500 cm) was immersed in 1L of Impregnant D for 20 minutes at 40° C.as the impregnation step. Then, the specimen was centrifuged at rotationrate of 1000 rpm and the weight increase in the specimen caused by theimpregnation step was about 4%. The specimen was exposed to ozone for 20minutes as the activation step. Then, as the hydrophilic polymertreatment step, the specimen was treated with an aqueous solution (500ml) of CMC (6.5 g) and KPS (0.5 g) four 2 hours at 80° C. The specimenwas washed with water. Then, the specimen was put in a mixture of water(500 ml), CAN (0.5 g) and acrylic acid (50 ml) four two hours at 80° C.The obtained specimen was washed with a water for 10 minutes at 60° C.,a boiling aqueous detergent solution and washed with water, and dried.The water absorption obtained by the water absorption test for thetreated fabric was 160% and the water absorption rate was 4.0 cm/min.The water absorption of the untreated fabric was 40% and its waterabsorption rate was 0 cm/min. In order to see the battery separatorusage, the following tests were examined. The obtained specimen did notgive a decrease in water absorption percentage and a decrease in tensilestrength in the alkali-resistance test, the acid-resistance test and theoxidant-resistance test. In the washing test of the obtained specimen,no decrease was observed in the water absorption percentage, the waterabsorption rate and the water retaining property.

Battery Separator Example 6

Preparation of Lead Storage Battery Separator by the Treatment of GlassFiber/PP of Sample 8 by the Modification Method 2

The same procedure as Example for battery separator 4 was followed,except that the specimen of Sample 8 was used and except that theImpregnant B was used for the impregnation step.

Battery Separator Example 7

Preparation of Lead Storage Battery Separator by the Treatment of PPNon-woven

Fabric 3 by the Modification Method 1

The of PP non-woven fabric 3 (weight 520 g), Sample 7 in Table 1 (size77 mm×5 m) was used and its impregnation process was carried out in thesame procedure as Example for battery separator 1. As the activationprocess, the specimen was exposed to ozone for 30 minutes. Then, thespecimen was put in a cylindrical reaction vessel, and methanol (30 ml),AIBN (100 mg) and acrylic acid (20 ml) were added in the vessel. Thethermal grafting was carried out at nitrogen atmosphere by allowing tostand it for 3 hours at 80° C. Basic experimental procedures weresimilar to those in Example for battery separator1. The weight increasein the specimen by grafting was 4%. The chemical resistance of thespecimen necessary for the battery separator use was evaluated asfollows. The obtained specimen did not give a decrease in waterabsorption percentage and a decrease in tensile strength in thealkali-resistance test and the acid-resistance test. Theoxidant-resistance test: after sufficient washing and drying, the waterabsorption of the specimen was 470%. Its tensile strength was 1.47 kg.These values were not changed before and after the test.

Battery Separator Example 8

Processing of Sample 17 by Modification Method 3.

A porous PE film (Sample 17) was immersed in Impregnant E as theimpregnation treatment for 10 minutes at 50° C. The specimen was treatedby a plasma treatment for 30 seconds. As the polymer treatment step, thespecimen was dipped in an aqueous PVA solution for one hour. Thegrafting to the specimen was carried out with CAN and acrylic acid bythe UV irradiation for one hour at 30° C. The washing method and theevaluation of the performance were made by the same way as described inExample for battery separator 3. The obtained specimen gave theexcellent property in a water absorption, a tensile strength and analkali-resistance.

Battery Separator Example 9

Evaluation Test 1 for Alkali Battery Separator

A Ni—Cd battery (a nominal capacity: 4Ah) was made using the hydrophilicPP non-woven fabric prepared in Example for battery separator 2 as abattery separator. Similarly to this, batteries using the non-wovenfabrics for battery separators obtained in Comparative Examples 1 and 2were prepared. The charge curves for these batteries examined by arepeated overcharge at 60° C. are given in FIG. 2. The inner resistanceof the battery incorporated with the non-woven fabric of the presentinvention was observed to be smaller than the materials obtained byBattery Separator Examples 1 and 2. In addition, the charge/dischargeperformance of the battery with the separator prepared by the presentinvention at high temperature was more excellent than that with thesurfactant-impregnated polypropylene non-woven fabric prepared inBattery Separator Comparative Example 2. Besides, this property was notchanged after the charge/discharge repeated five times. The separator ofthe present invention detached from the battery gave an excellentelectrolyte absorption property (electrolytic solution absorption:655%), but that of the surfactant impregnated PP/PE non-woven fabric ofBattery Separator Comparative Example 2 gave a decrease (electrolyticsolution absorption: 10%). In addition, it is well known that a nylonnon-woven fabric of Battery Separator Comparative Example 1 cannot beara long-time use.

Battery Separator Example 10

Evaluation Test for the Performance of Alkali Battery Separators 2

The evaluation test for the performance of alkali battery separators wascarried out for the materials of Battery Separator Examples 1 and 3 andBattery Separator Comparative Example 2. Treated specimens wereincorporated in a sealed nickel-hydrogen battery of a coin-size (anominal capacity: 500 mAh), and nine batteries were prepared. When theproperty of the batteries looked stable, they were charged to 120% ofthe capacity by an electric source of 0.1 C (Coulomb). After four cyclesof charge-discharge processes, the percentage of an average value of aresidual capacity (C) to the original value for each of batteries wasestimated after two weeks at 45° C. The observed values are listed inTable 3. In order to use as a preferable alkali battery separator, thehydrophilic treated material needs the excellent property in theelectrolytic solution absorption, the alkali-resistance, theacid-resistance and the charge-discharge performance. As the BatterySeparator Examples 1 an 2 gave an excellent electrolytic solutionabsorption, they are preferable for the alkali battery separators. Onthe other hand, the well-known surfactant-containing PP/PE non-wovenfabrics gave a low electrolytic solution absorption.

Battery Separator Comparative Example 3

Durability Test of Water Absorption Property of Sample 8

Sample 8 in Table 1 is a material which is composed of glass fibers(average diameter 20 microns) bonded simply by melting polyethylenefiber (average diameter 1-2 microns) and solidified by a water-solubleadhesive. As a fact, this material is used for the lead storagebatteries. This material gave a water absorption of 730%. When one sheetof Sample 8 (size 77 mm×145 mm, weight 2.64 g) was dipped in 500 ml ofboiling water for 5 minutes, the fibers of the material were raveledout. Thus, it was impossible to use this material.

Battery Separator Comparative Example 4

Grafting of acrylic acid to PP/PE non-woven fabric by well-known UVirradiation

PP/PE non-woven fabric (weight 1.2 g), Sample 3 in Table 1 (size 7.7cm×10 cm) was put in a reaction vessel containing acrylic acid monomer20.0%, water 78.8%, benzophenone 0.2% and methanol 1.0% (each %represents weight %), and the reaction mixture was exposed by the UVirradiation for 60 minutes. After the reaction, the product was jelledwith resulted polymers, but when the product was washed with a boilingaqueous soap solution for 10 minutes and washed with water, the polymerswere dissolved in the washing process. The water absorption percentageof the treated non-woven fabric was 100% (that of the untreatednon-woven fabric was 48%). Its grafting percentage was 1%. Namely, thewell-known grafting method by the UV irradiation gave a large apparentgrafting %, but the homopolymer of acrylic acid was removed from thefabric by the dissolution by washing with boiling water. The obtainedspecimen here was not suitable for a battery separator use, because theproperty of retaining electrolytic solutions was low and its durabilitywas not preferable.

Comparative Example for Battery Separator 5

Glass fiber separater

A separator of glass fiber non-woven fabric with an acid resistancewhich is extensively used for a sealed-type lead storage battery wasexamined. This separator is impregnated with a surfactant to get a goodwettablity at the initial stage. The separator is 1.0 mm thick, unitweight 342 g/m2, apparent density 0.20 g/c m³, fiber diameter 10microns, fiber length 4-8 cm, volume of vacancy 93%; it gave a waterabsorption of 780%.

Battery Separator Example 11

Evaluation test for the performance of a separator for lead-storagebatteries

Sealed-type lead storage batteries which were incorporated withseparators prepared in Battery Separator Examples 6 and 7 or a glassfiber battery separator prepared in Battery Separator ComparativeExample 5 were made as a test. The sealed-type lead storage battery gavea voltage 4 V and a capacity 3.8 Ah. As a discharge test, the time whenthe final voltage indicated 2.8 V at a discharge current 13 A wasobserved. Charge-discharge tests were repeated and the result of theelectrical property were listed in Table 4. In addition, the separatorsfor the lead storage battery prepared in Battery Separator Examples 6and 7 gave a more excellent durability.

As described in the above results, the lead storage battery used withthe hydrophilic polyolefin non-woven fabric prepared by the method ofthe present invention gave more excellent property in aliquid-retaining, a longer life-time and a lightweight than theconventional lead storage battery.

INDUSTRIAL APPLICABILITY

As described above, various polymeric materials improved by the presentinvention gave an excellent water absorption property and a goodadhesion property with adhesives without the decrease in strength.Besides, the property obtained by this modification gave an excellentdurability. In addition, the polyolefin filter of which hydrophilicproperty was modified by the present invention gave a development of theuse in the filtration of aqueous solutions. As the material improved bythe present invention gives a water absorption property and an excellentadhesion property to synthetic papers, the improvement of printingproperty of them is also expected. As the adhesion property of manykinds of polymeric materials containing carbon fibers is extremelyimproved, hydrophilic materials available for reinforcing fibers forcomposite materials can be obtained by the present invention. As thehydrophilic property of various kinds of polymeric materials can beimproved by the present invention, the present invention can be usefulto improve the property of various kinds of medical, sanitary, orcosmetic supplies and textile products for clothing, an adhesionproperty of orthodontic brackets made of polymers and the wettability towater for the medical supplies or instruments.

Although the kind of polymers useful for the production of the membersfor writing implements such as marker pens, fountain pens, brush pens,and so forth has been limited, the prevent invention can enable to usemany kinds of polymers containing polyolefins such as polypropylene,polyethylene, and so forth of which modification is considered to bedifficult for the production of the writing implements. The preventinvention can give the materials having the property of a safety, anacid-resistance and an alkali-resistance, which was not seen so far.

In addition, the present invention can provide battery separators whichhave the excellent property in an absorption property of electrolyticsolutions, an acid-resistance, an alkali-resistance and a physicalstrength, easily and with a cheap price. In addition, the batteriesproduced by using the separators prepared by the method of the presentinvention do not lose the excellent property for a long period.

TABLE 1 Fiber Tensile Thick- Unit dia- Strength Fiber Main ness weightmeter kg/15 mm length Density Voids Production Sample Name material μmg/m² μm width cm g/cm³ % method 1 PP non- PP 150 50 12.5 5.35 Continuing0.33 63 Spun bond woven fabric1 2 PP non- PP 210 45 12.5 1.8 ContinuingMelt blow woven fabric2 3 PP/PE non- PP/PE 300 76 6.2 8.03 3-6 0.25 72Heat set woven fabric water slip 4 PET non- PET 380 57 12.5 ContinuingMelt blow woven fabric 5 PP plain PP 120 150 20 1.21 1   Warp 40/cmfabric Weft 30/cm 6 PP/PET non- PP/PET 150 27 3.6 5.1 Spun bond wovenfabric 7 PP non- PP 1000 200 12.5 1.45 1   0.2 78 Spun bond wovenfabric3 8 Glass fiber/ Glass fiber/ 1000 213 201-2 1.68 1-5 0.39 Heatfusing PE PE fiber 9 Carbon fiber Carbon 150 50 1.4 Continuing 0.2Acrylic fiber fiber bundle raw material 10 Wool fiber Wool 500 188 8.88fabric 11 PP film PP 20 17 2.39 Spun bond 12 PET fiIm PET 60 72 11.6Spun bond 13 HMPE plate Super high 700 467 Average-Mwt Mwt PE 6 billion14 PP synthetic PP 130 92 17.9 White with paper air bubbles 15 Porous PESuper high 60 30 1.97 Average-Mwt 5 billion film Mwt PE Average voidsize = 1 μm 16 Porous PSU PSU 170 50 0.91 Average void size = 2 μm film17 Porous PE Super high 15 7.7 Average-Mwt 5 billion film Mwt PE Averagevoid size = 60 nm Remarks; Mwt: molecular weight

TABLE 2 Impregnant process Activation process Grafting Polymeric Temp.Time Temp. Time Temp. Time Example material Impregnant ° C. min. Method° C. min. Method Monomer ° C. min. Example 1 PPn.w.f.l A 50 10 OZ 20 30UV/CAN AA 30 2 Example 2 PPn.w.f.l B 50 10 PL 20 0.5 UV/CAN MA 30 2Example 3 PPn.w.f.l F 50 10 UV 30 60 UV/CAN AA 30 2 C. Exam. 1 PPn.w.f.lC. Exam. 2 PPn.w.f.l OZ 30 30 UV/CAN AA 30 2 C. Exam. 3 PPn.w.f.l UV/CANAA 30 2 C. Exam. 4 PPn.w.f.l OZ 30 30 C. Exam. 5 PPn.w.f.l A 50 10UV/CAN AA 30 2 Example 4 PP Plain c. C 50 10 PL 30 0.5 UV/CAN AA 30 2 C.Exam. 6 PP Plain c. C. Exam. 7 PP Plain c. PL 30 0.5 Example 5 PETn.w.f.Carrier 2 50 12 OZ 20 30 Heat/AIBN AA 80 2 Example 6 PETn.w.f. A 30 5 OZ20 30 UV MMA 30 2 C. Exam. 8 PETn.w.f. C. Exam. 9 PETn.w.f. OZ 20 30UV/CAN AA 30 2 C. Exam. 10 PETn.w.f. UV/CAN AA 30 4 C. Exam. 11PETn.w.f. OZ 20 30 C. Exam. 12 PETn.w.f. A 30 5 Example 7 P/E n.w.f. C50 10 PL 30 0.5 CAN MA 80 2 Example 8 P/E n.w.f. E 50 10 PL 30 0.5 KPSAA 30 2 C. Exam. 13 P/E n.w.f. Example 9 PET film E 70 15 OZ 20 30 UV AA30 2 C. Exam. 14 PET film C. Exam. 15 PET film OZ 20 30 UV AA 30 2 C.Exam. 16 PET film UV/CAN AA 30 2 C. Exam. 17 PET film OZ 20 45 C. Exam.18 PET film E 70 15 UV AA 30 2 Example 10 HMPE plate B 70 15 OZ 20 45UV/CAN AA 30 2 C. Exam. 19 HMPE plate C. Exam. 20 HMPE plate OZ 20 45UV/CAN AA 30 2 C. Exam. 21 HMPE plate UV/AIBN AA 30 2 C. Exam. 22 HMPEplate OZ 20 45 C. Exam. 23 HMPE plate A 70 15 OZ 20 45 UV/AIBN AA 30 2Example 11 PP film C 70 15 PL 30 0.5 UV/AIBN AA 30 2 C. Exam. 24 PP filmC. Exam. 25 PP film PL 30 0.5 UV/AIBN AA 30 2 C. Exam. 26 PP filmUV/AIBN AA 30 2 C. Exam. 27 PP film PL 30 0.5 C. Exam. 28 PP film A 7015 UV/AIBN AA 30 2 Water Water Water Peel- Polymeric absorption absptionabsption strength Contact Example material 1% rate mm/min. 3% ofadhesion angle ° Example 1 PPn.w.f.l 310 20 305 Example 2 PPn.w.f.l 30018 290 Example 3 PPn.w.f.l 300 20 298 C. Exam. 1 PPn.w.f.l 5 0 5 C.Exam. 2 PPn.w.f.l 80 0 60 C. Exam. 3 PPn.w.f.l 80 0 60 C. Exam. 4PPn.w.f.l 8 0 6 C. Exam. 5 PPn.w.f.l 70 0 50 Example 4 PP Plain c. 32015 310 C. Exam. 6 PP Plain c. 2 0 2 C. Exam. 7 PP Plain c. 80 0 60Example 5 PETn.w.f. 1100 18 1000 Example 6 PETn.w.f. C. Exam. 8PETn.w.f. 100 0 100 C. Exam. 9 PETn.w.f. 400 5 350 C. Exam. 10 PETn.w.f.320 3 290 C. Exam. 11 PETn.w.f. 110 0 110 C. Exam. 12 PETn.w.f. 300 4240 Example 7 P/E n.w.f. 800 18 780 Example 8 P/E n.w.f. 750 20 720 C.Exam. 13 P/E n.w.f. 5 0 5 Example 9 PET film 63 90 4 C. Exam. 14 PETfilm 85 9 1 C. Exam. 15 PET film 75 60 1.71 C. Exam. 16 PET film 80 681.41 C. Exam. 17 PET film 71 64 1.5 C. Exam. 18 PET film 81 10 1.71Example 10 HMPE plate 76 220 167 C. Exam. 19 HMPE plate 105 3 1 C. Exam.20 HMPE plate 81 18 1.3 C. Exam. 21 HMPE plate 90 5 1.2 C. Exam. 22 HMPEplate 91 6 1.1 C. Exam. 23 HMPE plate 92 10 1.3 Example 11 PP film 86280 33 C. Exam. 24 PP film 100 20 1 C. Exam. 25 PP film 91 181 21 C.Exam. 26 PP film 95 80 13 C. Exam. 27 PP film 95 20 2.7 C. Exam. 28 PPfilm 96 20 15 Remarks; C. Exam.: Comparative Example , n.w.f.: non-wovenfabris, c: cloth.

TABLE 3 Retention of Retention of Alkali-re- Capacity electrolyticelectrolytic sistance after Solution at a solution (Decrease self-initial stage after the in weight discharge Examples (%) test (%) (%))(%) Separator 201 190 0.1 90 Example 1 Separator 160 160 0.1 91 Example2 Separator Comparative 400 20 3 65 Example 2

TABLE 4 Separator Separator Separator Comparative Item Example 6 Example7 Example 5 Hydrophilic Sample 8 Sample 7 Acid-resistance material Glassfiber/PP PP Glass fiber Electric 0.009 0.0007 0.0009 resistance (ohmdm²/cell) Discharge  218 minutes  241 minutes  240 minutes capacity atfive hours high rate  118 seconds  132 seconds  130 seconds Dischargecapacity At low temperature Voltage at 1.62 V 1.58 V 1.57 V 5 secondsInitial water  7.0 cm/minute  5.0 cm/minute  7.2 cm/minute absorptionrate Water  6.5 cm/minute  5.0 cm/minute  4.8 cm/minute absorption rateafter 3 months Initial water 774% 643% 780% retension Water 740% 640%460% retention after 3 months

1. A method of modifying the surface of a polymeric surface of apolymeric material which comprises: (1) subjecting the polymericmaterial to an impregnation step to contact the polymeric material witha single or a mixture of compounds, having an impregnation property tothe polymeric material in the manner so that the compound permeates inthe polymeric material and the content of the impregnated compound inthe layer of polymeric material within the depth of 100 micron from thesurface of the polymeric material is in the range of 0.1% to 40% byweight of the treated polymeric material without any substantialdeformation of the polymeric material; (2) subjecting the polymericmaterial produced in said impregnation step to an activation step tointroduce carbonyl groups into the polymeric material, wherein saidactivation step is conducted by at least one treatment selected from thegroup consisting of an ozone treatment, a plasma treatment, a UVirradiation treatment, a corona discharge treatment and a high voltageelectric discharge treatment; and (3) conducting a step of monomergrafting to the polymeric material produced in said impregnation stepand subsequent said activation step, in the presence of catalysts orinitiators or photo-sensitizers, wherein said steps (1), (2) and (3) aresequentially carried out.
 2. A method of modifying the surface of apolymeric material which comprises: (1) subjecting the polymericmaterial to an impregnation step to contact the polymeric material witha single or a mixture of compounds, having an impregnation property tothe polymeric material in the manner so that the compound permeates inthe polymeric material and the content of the impregnated compound inthe layer of polymeric material within the depth of 100 micron from thesurface of the polymeric material is in the range of 0.1% to 40% byweight of the treated polymeric material without any substantialdeformation of the polymeric material; (2) subjecting the polymericmaterial produced in said impregnation step to an activation step tointroduce carbonyl groups into the polymeric material, wherein saidactivation step is conducted by at least one treatment selected from thegroup consisting of an ozone treatment, a plasma treatment, a UVirradiation treatment, a corona discharge treatment and a high voltageelectric discharge treatment; and (3) subjecting the polymeric materialproduced in said impregnation step and subsequent said activation stepto a step of treatment with hydrophilic polymers, in the presence ofcatalysts or initiators, wherein said step (1), (2) and (3) aresequentially carried out.
 3. A method of modifying the surface of apolymeric material which comprises: (1) subjecting the polymericmaterial to an impregnation step to contact the polymeric material witha single or a mixture of compounds, having an impregnation property tothe polymeric material in the manner so that the compound permeates inthe polymeric material and the content of the impregnated compound inthe layer of polymeric material within the depth of 100 micron from thesurface of the polymeric material is in the range of 0.1% to 40% byweight of the treated polymeric material without any substantialdeformation of the polymeric material; (2) subjecting the polymericmaterial produced in said impregnation step to an activation step tointroduce carbonyl groups into the polymeric material, wherein saidactivation step is conducted by at least one treatment selected from thegroup consisting of an ozone treatment, a plasma treatment, a UVirradiation treatment, a corona discharge treatment and a high voltageelectric discharge treatment; (3) subjecting the polymeric materialproduced in said impregnation step and subsequent said activation stepto a step of treatment with hydrophilic polymers, in the presence ofcatalysts or initiators; and (4) conducting a step of monomer graftingto the polymeric material produced in said impregnation step, in thepresence of catalysts or initiators or photo-sensitizers, subsequentsaid activation step and subsequent said step of treatment withhydrophilic polymers, wherein said steps (1), (2), (3) and (4) aresequentially carried out.
 4. The method according to any one of claim 1to 3, wherein said polymeric materials are in the form of any one offibers, woven fabrics, knotted webs, non-woven fabrics, boards, rods,films, sheets, porous films, and members of products of molded materialsin a given shape or composite materials with the other materials.
 5. Themethod according to any one of clams 1 to 3, wherein said polymericmaterials contain at least one or more kinds of anti-oxidants orstabilizers.
 6. The method according to any one of claim 1 to 3, whereinsaid impregnation step is conducted at a temperature below the meltingpoint or the softening point of the polymeric materials.
 7. The methodaccording to claim 1 or claim 3, wherein said monomer in said monomergrafting step is a compound having a carbon-carbon double bond.
 8. Themethod according to claim 1 or claim 3, wherein said monomer is at leastone monomer selected from the group consisting of acrylic acid,methacrylic acid, vinyl acetate, 2-butene acid, ethylene sulfonic acid,hydroxyalkyl acrylate, hydroxyalkyl methacrylate, acryl amide, vinylpyridine, vinyl pyrrolidone, vinyl carbazole, maleic anhydride andpyromellitic dianhydride.
 9. The method according to claim 2 or claim 3,wherein said hydrophilic polymer is at least one of the polymersselected from the group consisting of polyvinylalcohol,carboxymethylcellulose, polyhydroxy ethylmethacrylate, poly-α-hydroxyvinylalcohol, polyacrylic acid, polyvinyl pyrrolidone, polyalkyleneglycols, starch, glucomannan, silk fabroin, sencin, agar, egg white andsodium arginate.
 10. The method according to claim 1 or claim 3, whereinsaid step of monomer grafting is carried out by at least any one of ormore of the following methods: (1) heating and (2) UV irradiation. 11.The method according to claim 10, wherein said initiators are at leastone compound selected from the group consisting of peroxides, ceriumanimonium nitrate (IV), persulfates, oxidation-reduction catalysts andthe other initiators for radical polymerization.
 12. Polymeric materialobtained by the modification method according to any one of claim 1 to3.
 13. Wiping/cleansing materials, materials for filters, waterabsorption materials, water retention materials, synthetic papers,medicallsanitary/cosmetic supplies, materials for medical supplies orinstruments, and materials for microorganism culture media containingmodified polymeric materials obtained by the modification methodaccording to any one of claims 1 to
 3. 14. Writing materials containingmodified polymeric materials obtained by the modification methodaccording to any one of claim 1 to
 3. 15. Writing implements containingat least one writing material described in claim
 14. 16. Dentitionorthodontic appliances containing modified polymeric materials obtainedby the modification method according to any one of claims 1 to
 3. 17.Battery separators containing modified polymeric materials obtained bythe modification method according to any one of claim 1 to 3 andbatteries in which said battery separators are used.
 18. The methodaccording to claim 2 or claim 3, wherein said initiators are at leastone compound selected from the group consisting of peroxides, ceriumammonium nitrate (IV), persulfates, oxidation-reduction catalysts andthe other initiators for radical polymerization.